CVE-2026-31469

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-31469", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.097Z", "datePublished": "2026-04-22T13:53:58.266Z", "dateUpdated": "2026-11-10T12:44:32.036Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:22:48.560Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio_net: Fix UAF on dst_ops when IFF_XMIT_DST_RELEASE is cleared and napi_tx is false\n\nA UAF issue occurs when the virtio_net driver is configured with napi_tx=N\nand the device's IFF_XMIT_DST_RELEASE flag is cleared\n(e.g., during the configuration of tc route filter rules).\n\nWhen IFF_XMIT_DST_RELEASE is removed from the net_device, the network stack\nexpects the driver to hold the reference to skb->dst until the packet\nis fully transmitted and freed. In virtio_net with napi_tx=N,\nskbs may remain in the virtio transmit ring for an extended period.\n\nIf the network namespace is destroyed while these skbs are still pending,\nthe corresponding dst_ops structure has freed. When a subsequent packet\nis transmitted, free_old_xmit() is triggered to clean up old skbs.\nIt then calls dst_release() on the skb associated with the stale dst_entry.\nSince the dst_ops (referenced by the dst_entry) has already been freed,\na UAF kernel paging request occurs.\n\nfix it by adds skb_dst_drop(skb) in start_xmit to explicitly release\nthe dst reference before the skb is queued in virtio_net.\n\nCall Trace:\n Unable to handle kernel paging request at virtual address ffff80007e150000\n CPU: 2 UID: 0 PID: 6236 Comm: ping Kdump: loaded Not tainted 7.0.0-rc1+ #6 PREEMPT\n ...\n percpu_counter_add_batch+0x3c/0x158 lib/percpu_counter.c:98 (P)\n dst_release+0xe0/0x110 net/core/dst.c:177\n skb_release_head_state+0xe8/0x108 net/core/skbuff.c:1177\n sk_skb_reason_drop+0x54/0x2d8 net/core/skbuff.c:1255\n dev_kfree_skb_any_reason+0x64/0x78 net/core/dev.c:3469\n napi_consume_skb+0x1c4/0x3a0 net/core/skbuff.c:1527\n __free_old_xmit+0x164/0x230 drivers/net/virtio_net.c:611 [virtio_net]\n free_old_xmit drivers/net/virtio_net.c:1081 [virtio_net]\n start_xmit+0x7c/0x530 drivers/net/virtio_net.c:3329 [virtio_net]\n ...\n\nReproduction Steps:\nNETDEV=\"enp3s0\"\n\nconfig_qdisc_route_filter() {\n tc qdisc del dev $NETDEV root\n tc qdisc add dev $NETDEV root handle 1: prio\n tc filter add dev $NETDEV parent 1:0 \\\n\tprotocol ip prio 100 route to 100 flowid 1:1\n ip route add 192.168.1.100/32 dev $NETDEV realm 100\n}\n\ntest_ns() {\n ip netns add testns\n ip link set $NETDEV netns testns\n ip netns exec testns ifconfig $NETDEV 10.0.32.46/24\n ip netns exec testns ping -c 1 10.0.32.1\n ip netns del testns\n}\n\nconfig_qdisc_route_filter\n\ntest_ns\nsleep 2\ntest_ns"}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable virtio_net transmit/free path is reached through local packet transmission plus local netlink/ethtool namespace setup on a virtio_net interface. Remote traffic alone does not provide the required control over tc/qdisc, TX NAPI state, and namespace/device lifecycle.\nAC:L - The required conditions are attacker-controllable once the attacker has the needed network administration rights: disable TX NAPI, clear IFF_XMIT_DST_RELEASE via tc route filtering, queue packets, destroy the namespace, then trigger another transmit. There is no uncontrollable race; the pending-ring timing can be induced with normal traffic.\nPR:L - The setup requires CAP_NET_ADMIN for tc/qdisc, ethtool coalescing, and net namespace/device operations. In a reasonable delegated container or network-namespace deployment with a virtio_net interface, that maps to low privileges rather than init-namespace root, and uncertainty is resolved toward higher severity.\nUI:N - No victim user action is required after the attacker has the relevant local privileges. The attacker can perform the configuration, traffic generation, namespace teardown, and retrigger steps directly.\nS:U - The bug is in the kernel networking/virtio_net path and impacts the same kernel security authority. This is not a VM escape, IOMMU bypass, or other cross-scope boundary by itself.\nC:H - This is a use-after-free involving dst_ops referenced from an skb-held dst_entry after namespace teardown. Kernel UAFs are treated as high confidentiality impact because freed object reuse can enable memory disclosure primitives.\nI:H - The stale dst_ops/percpu-counter access is memory corruption in kernel context. As a kernel UAF, it is defensibly treated as exploitable for control-flow or write-primitive development.\nA:H - The reported failure is a kernel paging request/oops in dst_release via free_old_xmit. Even without full exploitation, the UAF can crash the kernel, causing high availability impact."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/net/virtio_net.c"], "versions": [{"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "be0e63f3b97bbaf453c542e8a15ba2a536e2ac01", "status": "affected", "versionType": "git"}, {"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "c1ec36cb3768574b916f20d2d7415fd14fa1bf12", "status": "affected", "versionType": "git"}, {"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "8a4790850e710fd6771e4d2112168ed1dd6c0e54", "status": "affected", "versionType": "git"}, {"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "fedd2e1630cac920844997227ccbe7b26a76375a", "status": "affected", "versionType": "git"}, {"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "f04733c4dc40c43899c3d1c97afbae5831a3770f", "status": "affected", "versionType": "git"}, {"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "9a18629f2525781f0f3dda7be72b204e4cf77d08", "status": "affected", "versionType": "git"}, {"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "63d45077b97bb0e0fe0c75931acbbca7a47af141", "status": "affected", "versionType": "git"}, {"version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "ba8bda9a0896746053aa97ac6c3e08168729172c", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/net/virtio_net.c"], "versions": [{"version": "2.6.26", "status": "affected"}, {"version": "0", "lessThan": "2.6.26", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.253", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.203", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.168", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.131", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.80", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.21", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.11", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "5.10.253"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "5.15.203"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.1.168"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.6.131"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.12.80"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.18.21"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.19.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/be0e63f3b97bbaf453c542e8a15ba2a536e2ac01"}, {"url": "https://git.kernel.org/stable/c/c1ec36cb3768574b916f20d2d7415fd14fa1bf12"}, {"url": "https://git.kernel.org/stable/c/8a4790850e710fd6771e4d2112168ed1dd6c0e54"}, {"url": "https://git.kernel.org/stable/c/fedd2e1630cac920844997227ccbe7b26a76375a"}, {"url": "https://git.kernel.org/stable/c/f04733c4dc40c43899c3d1c97afbae5831a3770f"}, {"url": "https://git.kernel.org/stable/c/9a18629f2525781f0f3dda7be72b204e4cf77d08"}, {"url": "https://git.kernel.org/stable/c/63d45077b97bb0e0fe0c75931acbbca7a47af141"}, {"url": "https://git.kernel.org/stable/c/ba8bda9a0896746053aa97ac6c3e08168729172c"}], "title": "virtio_net: Fix UAF on dst_ops when IFF_XMIT_DST_RELEASE is cleared and napi_tx is false", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"x_adpType": "supplier", 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Remote traffic alone does not provide the required control over tc/qdisc, TX NAPI state, and namespace/device lifecycle.\nAC:L - The required conditions are attacker-controllable once the attacker has the needed network administration rights: disable TX NAPI, clear IFF_XMIT_DST_RELEASE via tc route filtering, queue packets, destroy the namespace, then trigger another transmit. There is no uncontrollable race; the pending-ring timing can be induced with normal traffic.\nPR:L - The setup requires CAP_NET_ADMIN for tc/qdisc, ethtool coalescing, and net namespace/device operations. In a reasonable delegated container or network-namespace deployment with a virtio_net interface, that maps to low privileges rather than init-namespace root, and uncertainty is resolved toward higher severity.\nUI:N - No victim user action is required after the attacker has the relevant local privileges. The attacker can perform the configuration, traffic generation, namespace teardown, and retrigger steps directly.\nS:U - The bug is in the kernel networking/virtio_net path and impacts the same kernel security authority. This is not a VM escape, IOMMU bypass, or other cross-scope boundary by itself.\nC:H - This is a use-after-free involving dst_ops referenced from an skb-held dst_entry after namespace teardown. Kernel UAFs are treated as high confidentiality impact because freed object reuse can enable memory disclosure primitives.\nI:H - The stale dst_ops/percpu-counter access is memory corruption in kernel context. As a kernel UAF, it is defensibly treated as exploitable for control-flow or write-primitive development.\nA:H - The reported failure is a kernel paging request/oops in dst_release via free_old_xmit. Even without full exploitation, the UAF can crash the kernel, causing high availability impact."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "be0e63f3b97bbaf453c542e8a15ba2a536e2ac01", "versionType": "git"}, {"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "c1ec36cb3768574b916f20d2d7415fd14fa1bf12", "versionType": "git"}, {"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "8a4790850e710fd6771e4d2112168ed1dd6c0e54", "versionType": "git"}, {"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "fedd2e1630cac920844997227ccbe7b26a76375a", "versionType": "git"}, {"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "f04733c4dc40c43899c3d1c97afbae5831a3770f", "versionType": "git"}, {"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "9a18629f2525781f0f3dda7be72b204e4cf77d08", "versionType": "git"}, {"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "63d45077b97bb0e0fe0c75931acbbca7a47af141", "versionType": "git"}, {"status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "lessThan": "ba8bda9a0896746053aa97ac6c3e08168729172c", "versionType": "git"}], "programFiles": ["drivers/net/virtio_net.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "2.6.26"}, {"status": "unaffected", "version": "0", "lessThan": "2.6.26", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.253", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.203", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.168", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.131", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.80", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.21", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "6.19.11", "versionType": "semver", "lessThanOrEqual": "6.19.*"}, {"status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["drivers/net/virtio_net.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/be0e63f3b97bbaf453c542e8a15ba2a536e2ac01"}, {"url": "https://git.kernel.org/stable/c/c1ec36cb3768574b916f20d2d7415fd14fa1bf12"}, {"url": "https://git.kernel.org/stable/c/8a4790850e710fd6771e4d2112168ed1dd6c0e54"}, {"url": "https://git.kernel.org/stable/c/fedd2e1630cac920844997227ccbe7b26a76375a"}, {"url": "https://git.kernel.org/stable/c/f04733c4dc40c43899c3d1c97afbae5831a3770f"}, {"url": "https://git.kernel.org/stable/c/9a18629f2525781f0f3dda7be72b204e4cf77d08"}, {"url": "https://git.kernel.org/stable/c/63d45077b97bb0e0fe0c75931acbbca7a47af141"}, {"url": "https://git.kernel.org/stable/c/ba8bda9a0896746053aa97ac6c3e08168729172c"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio_net: Fix UAF on dst_ops when IFF_XMIT_DST_RELEASE is cleared and napi_tx is false\n\nA UAF issue occurs when the virtio_net driver is configured with napi_tx=N\nand the device's IFF_XMIT_DST_RELEASE flag is cleared\n(e.g., during the configuration of tc route filter rules).\n\nWhen IFF_XMIT_DST_RELEASE is removed from the net_device, the network stack\nexpects the driver to hold the reference to skb->dst until the packet\nis fully transmitted and freed. In virtio_net with napi_tx=N,\nskbs may remain in the virtio transmit ring for an extended period.\n\nIf the network namespace is destroyed while these skbs are still pending,\nthe corresponding dst_ops structure has freed. When a subsequent packet\nis transmitted, free_old_xmit() is triggered to clean up old skbs.\nIt then calls dst_release() on the skb associated with the stale dst_entry.\nSince the dst_ops (referenced by the dst_entry) has already been freed,\na UAF kernel paging request occurs.\n\nfix it by adds skb_dst_drop(skb) in start_xmit to explicitly release\nthe dst reference before the skb is queued in virtio_net.\n\nCall Trace:\n Unable to handle kernel paging request at virtual address ffff80007e150000\n CPU: 2 UID: 0 PID: 6236 Comm: ping Kdump: loaded Not tainted 7.0.0-rc1+ #6 PREEMPT\n ...\n percpu_counter_add_batch+0x3c/0x158 lib/percpu_counter.c:98 (P)\n dst_release+0xe0/0x110 net/core/dst.c:177\n skb_release_head_state+0xe8/0x108 net/core/skbuff.c:1177\n sk_skb_reason_drop+0x54/0x2d8 net/core/skbuff.c:1255\n dev_kfree_skb_any_reason+0x64/0x78 net/core/dev.c:3469\n napi_consume_skb+0x1c4/0x3a0 net/core/skbuff.c:1527\n __free_old_xmit+0x164/0x230 drivers/net/virtio_net.c:611 [virtio_net]\n free_old_xmit drivers/net/virtio_net.c:1081 [virtio_net]\n start_xmit+0x7c/0x530 drivers/net/virtio_net.c:3329 [virtio_net]\n ...\n\nReproduction Steps:\nNETDEV=\"enp3s0\"\n\nconfig_qdisc_route_filter() {\n tc qdisc del dev $NETDEV root\n tc qdisc add dev $NETDEV root handle 1: prio\n tc filter add dev $NETDEV parent 1:0 \\\n\tprotocol ip prio 100 route to 100 flowid 1:1\n ip route add 192.168.1.100/32 dev $NETDEV realm 100\n}\n\ntest_ns() {\n ip netns add testns\n ip link set $NETDEV netns testns\n ip netns exec testns ifconfig $NETDEV 10.0.32.46/24\n ip netns exec testns ping -c 1 10.0.32.1\n ip netns del testns\n}\n\nconfig_qdisc_route_filter\n\ntest_ns\nsleep 2\ntest_ns"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.253", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.203", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.168", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.131", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.80", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.21", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.19.11", "versionStartIncluding": "2.6.26"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.0", "versionStartIncluding": "2.6.26"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:22:48.560Z"}}}, "cveMetadata": {"cveId": "CVE-2026-31469", "state": "PUBLISHED", "dateUpdated": "2026-11-10T12:44:32.036Z", "dateReserved": "2026-03-09T15:48:24.097Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-04-22T13:53:58.266Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/net/virtio_net.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "be0e63f3b97bbaf453c542e8a15ba2a536e2ac01", "status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "versionType": "git"}, {"lessThan": "c1ec36cb3768574b916f20d2d7415fd14fa1bf12", "status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "versionType": "git"}, {"lessThan": "8a4790850e710fd6771e4d2112168ed1dd6c0e54", "status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "versionType": "git"}, {"lessThan": "fedd2e1630cac920844997227ccbe7b26a76375a", "status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", "versionType": "git"}, {"lessThan": "f04733c4dc40c43899c3d1c97afbae5831a3770f", "status": "affected", "version": "f2fc6a54585a1be6669613a31fbaba2ecbadcd36", 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"version": "5.15.203", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.168", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.131", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.80", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.21", "versionType": "semver"}, {"lessThanOrEqual": "6.19.*", "status": "unaffected", "version": "6.19.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"affectedData": [{"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.5", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.5", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.5", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.5", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.5", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}], "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "12FCCED5-075B-4D9E-9684-F4F99BF08DE6", "versionEndExcluding": "5.10.253", "versionStartIncluding": "2.6.26", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "20DDB3E9-AABF-4107-ADB0-5362AA067045", "versionEndExcluding": "5.15.203", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "E2DDDCA1-6DAB-4018-B920-8F045DDD8D3B", "versionEndExcluding": "6.1.168", "versionStartIncluding": "5.16", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "CE6ED4D4-0046-4573-BFA9-D64143B6A89F", "versionEndExcluding": 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"cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio_net: Fix UAF on dst_ops when IFF_XMIT_DST_RELEASE is cleared and napi_tx is false\n\nA UAF issue occurs when the virtio_net driver is configured with napi_tx=N\nand the device's IFF_XMIT_DST_RELEASE flag is cleared\n(e.g., during the configuration of tc route filter rules).\n\nWhen IFF_XMIT_DST_RELEASE is removed from the net_device, the network stack\nexpects the driver to hold the reference to skb->dst until the packet\nis fully transmitted and freed. In virtio_net with napi_tx=N,\nskbs may remain in the virtio transmit ring for an extended period.\n\nIf the network namespace is destroyed while these skbs are still pending,\nthe corresponding dst_ops structure has freed. When a subsequent packet\nis transmitted, free_old_xmit() is triggered to clean up old skbs.\nIt then calls dst_release() on the skb associated with the stale dst_entry.\nSince the dst_ops (referenced by the dst_entry) has already been freed,\na UAF kernel paging request occurs.\n\nfix it by adds skb_dst_drop(skb) in start_xmit to explicitly release\nthe dst reference before the skb is queued in virtio_net.\n\nCall Trace:\n Unable to handle kernel paging request at virtual address ffff80007e150000\n CPU: 2 UID: 0 PID: 6236 Comm: ping Kdump: loaded Not tainted 7.0.0-rc1+ #6 PREEMPT\n ...\n percpu_counter_add_batch+0x3c/0x158 lib/percpu_counter.c:98 (P)\n dst_release+0xe0/0x110 net/core/dst.c:177\n skb_release_head_state+0xe8/0x108 net/core/skbuff.c:1177\n sk_skb_reason_drop+0x54/0x2d8 net/core/skbuff.c:1255\n dev_kfree_skb_any_reason+0x64/0x78 net/core/dev.c:3469\n napi_consume_skb+0x1c4/0x3a0 net/core/skbuff.c:1527\n __free_old_xmit+0x164/0x230 drivers/net/virtio_net.c:611 [virtio_net]\n free_old_xmit drivers/net/virtio_net.c:1081 [virtio_net]\n start_xmit+0x7c/0x530 drivers/net/virtio_net.c:3329 [virtio_net]\n ...\n\nReproduction Steps:\nNETDEV=\"enp3s0\"\n\nconfig_qdisc_route_filter() {\n tc qdisc del dev $NETDEV root\n tc qdisc add dev $NETDEV root handle 1: prio\n tc filter add dev $NETDEV parent 1:0 \\\n\tprotocol ip prio 100 route to 100 flowid 1:1\n ip route add 192.168.1.100/32 dev $NETDEV realm 100\n}\n\ntest_ns() {\n ip netns add testns\n ip link set $NETDEV netns testns\n ip netns exec testns ifconfig $NETDEV 10.0.32.46/24\n ip netns exec testns ping -c 1 10.0.32.1\n ip netns del testns\n}\n\nconfig_qdisc_route_filter\n\ntest_ns\nsleep 2\ntest_ns"}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nvirtio_net: Correcci\u00f3n de UAF en dst_ops cuando IFF_XMIT_DST_RELEASE es borrado y napi_tx es falso\n\nUn problema de UAF ocurre cuando el controlador virtio_net est\u00e1 configurado con napi_tx=N y el flag IFF_XMIT_DST_RELEASE del dispositivo es borrado (p. ej., durante la configuraci\u00f3n de reglas de filtro de ruta tc).\n\nCuando IFF_XMIT_DST_RELEASE es eliminado del net_device, la pila de red espera que el controlador mantenga la referencia a skb -> dst hasta que el paquete sea completamente transmitido y liberado. En virtio_net con napi_tx=N, los skbs pueden permanecer en el anillo de transmisi\u00f3n virtio por un per\u00edodo extendido.\n\nSi el espacio de nombres de red es destruido mientras estos skbs a\u00fan est\u00e1n pendientes, la estructura dst_ops correspondiente ha sido liberada. Cuando un paquete subsiguiente es transmitido, free_old_xmit() es activado para limpiar los skbs antiguos. Luego llama a dst_release() en el skb asociado con el dst_entry obsoleto. Dado que el dst_ops (referenciado por el dst_entry) ya ha sido liberado, una solicitud de paginaci\u00f3n del kernel UAF ocurre.\n\nSe corrige a\u00f1adiendo skb_dst_drop(skb) en start_xmit para liberar expl\u00edcitamente la referencia dst antes de que el skb sea encolado en virtio_net.\n\nTraza de Llamada:\n No se puede manejar la solicitud de paginaci\u00f3n del kernel en la direcci\u00f3n virtual ffff80007e150000\n CPU: 2 UID: 0 PID: 6236 Comm: ping Kdump: loaded Not tainted 7.0.0-rc1+ #6 PREEMPT\n ...\n percpu_counter_add_batch+0x3c/0x158 lib/percpu_counter.c:98 (P)\n dst_release+0xe0/0x110 net/core/dst.c:177\n skb_release_head_state+0xe8/0x108 net/core/skbuff.c:1177\n sk_skb_reason_drop+0x54/0x2d8 net/core/skbuff.c:1255\n dev_kfree_skb_any_reason+0x64/0x78 net/core/dev.c:3469\n napi_consume_skb+0x1c4/0x3a0 net/core/skbuff.c:1527\n __free_old_xmit+0x164/0x230 drivers/net/virtio_net.c:611 [virtio_net]\n free_old_xmit drivers/net/virtio_net.c:1081 [virtio_net]\n start_xmit+0x7c/0x530 drivers/net/virtio_net.c:3329 [virtio_net]\n ...\n\nPasos de Reproducci\u00f3n:\nNETDEV=\u201cenp3s0\u201d\n\nconfig_qdisc_route_filter() {\n tc qdisc del dev $NETDEV root\n tc qdisc add dev $NETDEV root handle 1: prio\n tc filter add dev $NETDEV parent 1:0 \\\n\tprotocol ip prio 100 route to 100 flowid 1:1\n ip route add 192.168.1.100/32 dev $NETDEV realm 100\n}\n\ntest_ns() {\n ip netns add testns\n ip link set $NETDEV netns testns\n ip netns exec testns ifconfig $NETDEV 10.0.32.46/24\n ip netns exec testns ping -c 1 10.0.32.1\n ip netns del testns\n}\n\nconfig_qdisc_route_filter\n\ntest_ns\nsleep 2\ntest_ns"}], "id": "CVE-2026-31469", "lastModified": "2026-11-11T23:10:00.263", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-31469", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:09:47.364337Z", "version": "2.0.3"}}]}, "published": "2026-04-22T14:16:43.260", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/63d45077b97bb0e0fe0c75931acbbca7a47af141"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/8a4790850e710fd6771e4d2112168ed1dd6c0e54"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/9a18629f2525781f0f3dda7be72b204e4cf77d08"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/ba8bda9a0896746053aa97ac6c3e08168729172c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/be0e63f3b97bbaf453c542e8a15ba2a536e2ac01"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c1ec36cb3768574b916f20d2d7415fd14fa1bf12"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f04733c4dc40c43899c3d1c97afbae5831a3770f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/fedd2e1630cac920844997227ccbe7b26a76375a"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-416"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: virtio_net: Fix UAF on dst_ops when IFF_XMIT_DST_RELEASE is cleared and napi_tx is false", "id": "2460669", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2460669"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-911", "details": ["A flaw was found in the Linux kernel's virtio_net driver. A local user can trigger a Use-After-Free (UAF) vulnerability by configuring the driver with specific network settings and then destroying the network namespace while data packets are still being transmitted. This premature freeing of network resources, specifically the dst_ops structure, can lead to a kernel paging request, resulting in a system crash and a Denial of Service (DoS)."], "name": "CVE-2026-31469", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-04-22T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31469\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31469\nhttps://lore.kernel.org/linux-cve-announce/2026042254-CVE-2026-31469-65d8@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,be0e63f3b97bbaf453c542e8a15ba2a536e2ac01)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,c1ec36cb3768574b916f20d2d7415fd14fa1bf12)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,8a4790850e710fd6771e4d2112168ed1dd6c0e54)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,fedd2e1630cac920844997227ccbe7b26a76375a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,f04733c4dc40c43899c3d1c97afbae5831a3770f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,9a18629f2525781f0f3dda7be72b204e4cf77d08)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,63d45077b97bb0e0fe0c75931acbbca7a47af141)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2fc6a54585a1be6669613a31fbaba2ecbadcd36,ba8bda9a0896746053aa97ac6c3e08168729172c)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "2.6.26"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,2.6.26)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[5.10.253,5.11.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[5.15.203,5.16.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.168,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.131,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.80,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.21,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.11,6.20.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.0,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-04-22T16:45:21.251810+00:00", "updated": "2026-05-07T19:30:27.396723+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}