CVE-2026-68338

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-68338", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.384Z", "datePublished": "2026-08-10T12:03:14.549Z", "dateUpdated": "2026-10-19T21:09:05.428Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:33:38.308Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: avoid fanout hook re-registration after unregister\n\npacket_set_ring() temporarily detaches a socket from packet delivery while\nreconfiguring its ring. It records the previous running state, clears\npo->num, unregisters the protocol hook when needed, drops po->bind_lock,\nand later restores po->num and re-registers the hook from the saved\nwas_running value.\n\nThat unlocked window can race with NETDEV_UNREGISTER. The notifier can\nobserve the socket as not running, skip __unregister_prot_hook(), and\ninvalidate the per-socket binding by setting po->ifindex to -1 and clearing\npo->prot_hook.dev. A one-member fanout group can still retain its shared\nfanout hook device pointer. When packet_set_ring() resumes, re-registering\nsolely from the stale was_running state can re-add the fanout hook after\nthe device has been unregistered.\n\nTreat po->ifindex == -1 as an invalidated binding after reacquiring\npo->bind_lock. This is distinct from ifindex 0, the normal\nunbound/wildcard state: ifindex -1 marks an existing device binding that\nwas invalidated when the device was unregistered. Restore po->num as\nbefore, but do not re-register the hook if device unregister already\ndetached the socket."}], "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 bug is triggered through local syscalls \u2014 creating an AF_PACKET socket, PACKET_FANOUT/bind setsockopt, PACKET_RX_RING setsockopt, and a netlink device unregister \u2014 with no remote packet processing involved.\nAC:L - The attacker controls both sides of the race: it issues the packet_set_ring() reconfiguration and deletes the bound netdev in its own netns, and the unlocked window spans synchronize_net() plus the ring swap, making it wide and reliably winnable.\nPR:L - AF_PACKET requires CAP_NET_RAW and device unregistration CAP_NET_ADMIN, but an unprivileged user obtains both via user+network namespaces (unshare -Urn) and can create and delete veth/dummy devices there.\nUI:N - The attacker performs every step itself \u2014 socket setup, ring reconfiguration and device teardown \u2014 with no action required from any other user.\nS:U - The stale hook registration and resulting corruption stay within the kernel's own security authority; no hypervisor, IOMMU or other trust boundary is crossed.\nC:H - The fanout packet_type is left linked into a net_device that is being torn down, a dangling registration on soon-to-be-freed memory; such stale-pointer state in the ptype lists can be leveraged for kernel memory disclosure.\nI:H - The dangling list node in the freed net_device's ptype list yields a list_del write into freed memory when the hook is later removed, a controllable write primitive typical of use-after-free exploitation.\nA:H - The re-added hook makes netdev_run_todo() hit BUG_ON(!list_empty(&dev->ptype_all)) while RTNL is held, oopsing the kernel and permanently wedging all further network configuration \u2014 a repeatable, unprivileged host-wide denial of service."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/packet/af_packet.c"], "versions": [{"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "acb40ebfa5c4d62f84339fcbf713f2a9fd033a71", "status": "affected", "versionType": "git"}, {"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "c820f4b7f2fa38f8769db0d0cefdd94e2721504d", "status": "affected", "versionType": "git"}, {"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "4628efbdc7affd094181f5263e65c1062e31f15f", "status": "affected", "versionType": "git"}, {"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "80ec024d53a05c60ad1d08968dcf745f10c1665c", "status": "affected", "versionType": "git"}, {"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "0a052e0808e015e68144a9877e6ef42b952c49fa", "status": "affected", "versionType": "git"}, {"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "1bc55c29cd85818e9052f17deb287d5a11fb817f", "status": "affected", "versionType": "git"}, {"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "a885387dae7986a55bae5c77a15bdd447f64e9b9", "status": "affected", "versionType": "git"}, {"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "50aff80475abd3533eef4320477037e6fcc6b56e", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/packet/af_packet.c"], "versions": [{"version": "3.1", "status": "affected"}, {"version": "0", "lessThan": "3.1", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.148", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "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": "3.1", "versionEndExcluding": "5.10.265"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1", "versionEndExcluding": "5.15.216"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1", "versionEndExcluding": "6.1.183"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1", "versionEndExcluding": "6.6.148"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1", "versionEndExcluding": "6.12.101"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1", "versionEndExcluding": "6.18.42"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1", "versionEndExcluding": "7.1.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/acb40ebfa5c4d62f84339fcbf713f2a9fd033a71"}, {"url": "https://git.kernel.org/stable/c/c820f4b7f2fa38f8769db0d0cefdd94e2721504d"}, {"url": "https://git.kernel.org/stable/c/4628efbdc7affd094181f5263e65c1062e31f15f"}, {"url": "https://git.kernel.org/stable/c/80ec024d53a05c60ad1d08968dcf745f10c1665c"}, {"url": "https://git.kernel.org/stable/c/0a052e0808e015e68144a9877e6ef42b952c49fa"}, {"url": "https://git.kernel.org/stable/c/1bc55c29cd85818e9052f17deb287d5a11fb817f"}, {"url": "https://git.kernel.org/stable/c/a885387dae7986a55bae5c77a15bdd447f64e9b9"}, {"url": "https://git.kernel.org/stable/c/50aff80475abd3533eef4320477037e6fcc6b56e"}], "title": "net/packet: avoid fanout hook re-registration after unregister", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-68338", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:47:16.591778Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-362", "description": "CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-19T21:09:05.428Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-68338", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:47:16.591778Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-362", "description": "CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T15:47:17.184Z"}}], "cna": {"title": "net/packet: avoid fanout hook re-registration after unregister", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 7.8, "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:L - The bug is triggered through local syscalls \u2014 creating an AF_PACKET socket, PACKET_FANOUT/bind setsockopt, PACKET_RX_RING setsockopt, and a netlink device unregister \u2014 with no remote packet processing involved.\nAC:L - The attacker controls both sides of the race: it issues the packet_set_ring() reconfiguration and deletes the bound netdev in its own netns, and the unlocked window spans synchronize_net() plus the ring swap, making it wide and reliably winnable.\nPR:L - AF_PACKET requires CAP_NET_RAW and device unregistration CAP_NET_ADMIN, but an unprivileged user obtains both via user+network namespaces (unshare -Urn) and can create and delete veth/dummy devices there.\nUI:N - The attacker performs every step itself \u2014 socket setup, ring reconfiguration and device teardown \u2014 with no action required from any other user.\nS:U - The stale hook registration and resulting corruption stay within the kernel's own security authority; no hypervisor, IOMMU or other trust boundary is crossed.\nC:H - The fanout packet_type is left linked into a net_device that is being torn down, a dangling registration on soon-to-be-freed memory; such stale-pointer state in the ptype lists can be leveraged for kernel memory disclosure.\nI:H - The dangling list node in the freed net_device's ptype list yields a list_del write into freed memory when the hook is later removed, a controllable write primitive typical of use-after-free exploitation.\nA:H - The re-added hook makes netdev_run_todo() hit BUG_ON(!list_empty(&dev->ptype_all)) while RTNL is held, oopsing the kernel and permanently wedging all further network configuration \u2014 a repeatable, unprivileged host-wide denial of service."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "acb40ebfa5c4d62f84339fcbf713f2a9fd033a71", "versionType": "git"}, {"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "c820f4b7f2fa38f8769db0d0cefdd94e2721504d", "versionType": "git"}, {"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "4628efbdc7affd094181f5263e65c1062e31f15f", "versionType": "git"}, {"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "80ec024d53a05c60ad1d08968dcf745f10c1665c", "versionType": "git"}, {"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "0a052e0808e015e68144a9877e6ef42b952c49fa", "versionType": "git"}, {"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "1bc55c29cd85818e9052f17deb287d5a11fb817f", "versionType": "git"}, {"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "a885387dae7986a55bae5c77a15bdd447f64e9b9", "versionType": "git"}, {"status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "lessThan": "50aff80475abd3533eef4320477037e6fcc6b56e", "versionType": "git"}], "programFiles": ["net/packet/af_packet.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "3.1"}, {"status": "unaffected", "version": "0", "lessThan": "3.1", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.265", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.216", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.183", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.148", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.101", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.42", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.6", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/packet/af_packet.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/acb40ebfa5c4d62f84339fcbf713f2a9fd033a71"}, {"url": "https://git.kernel.org/stable/c/c820f4b7f2fa38f8769db0d0cefdd94e2721504d"}, {"url": "https://git.kernel.org/stable/c/4628efbdc7affd094181f5263e65c1062e31f15f"}, {"url": "https://git.kernel.org/stable/c/80ec024d53a05c60ad1d08968dcf745f10c1665c"}, {"url": "https://git.kernel.org/stable/c/0a052e0808e015e68144a9877e6ef42b952c49fa"}, {"url": "https://git.kernel.org/stable/c/1bc55c29cd85818e9052f17deb287d5a11fb817f"}, {"url": "https://git.kernel.org/stable/c/a885387dae7986a55bae5c77a15bdd447f64e9b9"}, {"url": "https://git.kernel.org/stable/c/50aff80475abd3533eef4320477037e6fcc6b56e"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: avoid fanout hook re-registration after unregister\n\npacket_set_ring() temporarily detaches a socket from packet delivery while\nreconfiguring its ring. It records the previous running state, clears\npo->num, unregisters the protocol hook when needed, drops po->bind_lock,\nand later restores po->num and re-registers the hook from the saved\nwas_running value.\n\nThat unlocked window can race with NETDEV_UNREGISTER. The notifier can\nobserve the socket as not running, skip __unregister_prot_hook(), and\ninvalidate the per-socket binding by setting po->ifindex to -1 and clearing\npo->prot_hook.dev. A one-member fanout group can still retain its shared\nfanout hook device pointer. When packet_set_ring() resumes, re-registering\nsolely from the stale was_running state can re-add the fanout hook after\nthe device has been unregistered.\n\nTreat po->ifindex == -1 as an invalidated binding after reacquiring\npo->bind_lock. This is distinct from ifindex 0, the normal\nunbound/wildcard state: ifindex -1 marks an existing device binding that\nwas invalidated when the device was unregistered. Restore po->num as\nbefore, but do not re-register the hook if device unregister already\ndetached the socket."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.265", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.216", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.183", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.148", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.101", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.42", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1.6", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.2", "versionStartIncluding": "3.1"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:33:38.308Z"}}}, "cveMetadata": {"cveId": "CVE-2026-68338", "state": "PUBLISHED", "dateUpdated": "2026-10-19T21:09:05.428Z", "dateReserved": "2026-07-30T09:28:09.384Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-08-10T12:03:14.549Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/packet/af_packet.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "acb40ebfa5c4d62f84339fcbf713f2a9fd033a71", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}, {"lessThan": "c820f4b7f2fa38f8769db0d0cefdd94e2721504d", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}, {"lessThan": "4628efbdc7affd094181f5263e65c1062e31f15f", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}, {"lessThan": "80ec024d53a05c60ad1d08968dcf745f10c1665c", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}, {"lessThan": "0a052e0808e015e68144a9877e6ef42b952c49fa", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}, {"lessThan": "1bc55c29cd85818e9052f17deb287d5a11fb817f", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}, {"lessThan": "a885387dae7986a55bae5c77a15bdd447f64e9b9", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}, {"lessThan": "50aff80475abd3533eef4320477037e6fcc6b56e", "status": "affected", "version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/packet/af_packet.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "3.1"}, {"lessThan": "3.1", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.265", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.216", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.183", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.148", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.101", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.42", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: avoid fanout hook re-registration after unregister\n\npacket_set_ring() temporarily detaches a socket from packet delivery while\nreconfiguring its ring. It records the previous running state, clears\npo->num, unregisters the protocol hook when needed, drops po->bind_lock,\nand later restores po->num and re-registers the hook from the saved\nwas_running value.\n\nThat unlocked window can race with NETDEV_UNREGISTER. The notifier can\nobserve the socket as not running, skip __unregister_prot_hook(), and\ninvalidate the per-socket binding by setting po->ifindex to -1 and clearing\npo->prot_hook.dev. A one-member fanout group can still retain its shared\nfanout hook device pointer. When packet_set_ring() resumes, re-registering\nsolely from the stale was_running state can re-add the fanout hook after\nthe device has been unregistered.\n\nTreat po->ifindex == -1 as an invalidated binding after reacquiring\npo->bind_lock. This is distinct from ifindex 0, the normal\nunbound/wildcard state: ifindex -1 marks an existing device binding that\nwas invalidated when the device was unregistered. Restore po->num as\nbefore, but do not re-register the hook if device unregister already\ndetached the socket."}], "id": "CVE-2026-68338", "lastModified": "2026-10-19T22:17:13.900", "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-2026-68338", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:47:16.591778Z", "version": "2.0.3"}}]}, "published": "2026-08-10T13:20:24.230", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0a052e0808e015e68144a9877e6ef42b952c49fa"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1bc55c29cd85818e9052f17deb287d5a11fb817f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4628efbdc7affd094181f5263e65c1062e31f15f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/50aff80475abd3533eef4320477037e6fcc6b56e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/80ec024d53a05c60ad1d08968dcf745f10c1665c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a885387dae7986a55bae5c77a15bdd447f64e9b9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/acb40ebfa5c4d62f84339fcbf713f2a9fd033a71"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c820f4b7f2fa38f8769db0d0cefdd94e2721504d"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-362"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: Linux kernel: net/packet fanout hook re-registration race condition leading to denial of service", "id": "2513264", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2513264"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.7", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-367", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nnet/packet: avoid fanout hook re-registration after unregister\npacket_set_ring() temporarily detaches a socket from packet delivery while\nreconfiguring its ring. It records the previous running state, clears\npo->num, unregisters the protocol hook when needed, drops po->bind_lock,\nand later restores po->num and re-registers the hook from the saved\nwas_running value.\nThat unlocked window can race with NETDEV_UNREGISTER. The notifier can\nobserve the socket as not running, skip __unregister_prot_hook(), and\ninvalidate the per-socket binding by setting po->ifindex to -1 and clearing\npo->prot_hook.dev. A one-member fanout group can still retain its shared\nfanout hook device pointer. When packet_set_ring() resumes, re-registering\nsolely from the stale was_running state can re-add the fanout hook after\nthe device has been unregistered.\nTreat po->ifindex == -1 as an invalidated binding after reacquiring\npo->bind_lock. This is distinct from ifindex 0, the normal\nunbound/wildcard state: ifindex -1 marks an existing device binding that\nwas invalidated when the device was unregistered. Restore po->num as\nbefore, but do not re-register the hook if device unregister already\ndetached the socket.", "A flaw was found in the Linux kernel's `net/packet` subsystem. A race condition can occur during the re-registration of a fanout hook after a network device has been unregistered. This issue arises when the `packet_set_ring()` function attempts to re-add a fanout hook based on a stale state, potentially leading to an inconsistent system state and a denial of service (DoS)."], "name": "CVE-2026-68338", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux_nvidia:", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux for NVIDIA 26"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "rhcos", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-08-10T12:03:14Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-68338\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-68338\nhttps://git.kernel.org/stable/c/0a052e0808e015e68144a9877e6ef42b952c49fa\nhttps://git.kernel.org/stable/c/1bc55c29cd85818e9052f17deb287d5a11fb817f\nhttps://git.kernel.org/stable/c/50aff80475abd3533eef4320477037e6fcc6b56e\nhttps://git.kernel.org/stable/c/80ec024d53a05c60ad1d08968dcf745f10c1665c\nhttps://git.kernel.org/stable/c/a885387dae7986a55bae5c77a15bdd447f64e9b9"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[dc99f600698dcac69b8f56dda9a8a00d645c5ffc,80ec024d53a05c60ad1d08968dcf745f10c1665c)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[dc99f600698dcac69b8f56dda9a8a00d645c5ffc,0a052e0808e015e68144a9877e6ef42b952c49fa)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[dc99f600698dcac69b8f56dda9a8a00d645c5ffc,1bc55c29cd85818e9052f17deb287d5a11fb817f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[dc99f600698dcac69b8f56dda9a8a00d645c5ffc,a885387dae7986a55bae5c77a15bdd447f64e9b9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[dc99f600698dcac69b8f56dda9a8a00d645c5ffc,50aff80475abd3533eef4320477037e6fcc6b56e)"}}], "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": "3.1"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,3.1)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.148,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.101,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.42,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.6,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2-rc5,*]"}}], "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": "2026-08-10T16:00:04.017026+00:00", "updated": "2026-10-20T10:45:13.778492+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}