CVE-2026-64032

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64032", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.028Z", "datePublished": "2026-07-19T15:39:22.228Z", "dateUpdated": "2026-10-19T20:28:09.740Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:38:26.376Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: mcast: Fix a possible use-after-free when removing a bridge port\n\nWhen per-VLAN multicast snooping is enabled, the bridge iterates over\nall the bridge ports, disables the per-port multicast context on each\nport and enables the per-{port, VLAN} multicast contexts instead. The\nreverse happens when per-VLAN multicast snooping is disabled.\n\nWhen global multicast snooping is enabled, the bridge iterates over all\nthe bridge ports and enables the per-port multicast context on each\nport. The reverse happens when multicast snooping is disabled.\n\nThe above scheme can result in a situation where both types of contexts\n(per-port and per-{port, VLAN}) are enabled on a single bridge port:\n\n # ip link add name br1 up type bridge mcast_snooping 1 mcast_querier 1 vlan_filtering 1\n # ip link add name dummy1 up master br1 type dummy\n # ip link set dev br1 type bridge mcast_vlan_snooping 1\n # ip link set dev br1 type bridge mcast_snooping 0\n # ip link set dev br1 type bridge mcast_snooping 1\n\nThis is not intended and it is a problem since the commit cited below.\nPrior to this commit, when removing a bridge port,\nbr_multicast_disable_port() would disable the per-port multicast context\nand the per-{port, VLAN} multicast contexts would get disabled when\nflushing VLANs.\n\nAfter this commit, br_multicast_disable_port() only disables the\nper-port multicast context if per-VLAN multicast snooping is disabled.\nIf both types of contexts were enabled on the port when it was removed,\nthe per-port multicast context would remain enabled when freeing the\nbridge port, leading to a use-after-free [1].\n\nFix by preventing the bridge from enabling / disabling the per-port\nmulticast contexts when toggling global multicast snooping if per-VLAN\nmulticast snooping is enabled.\n\n[1]\nODEBUG: free active (active state 0) object: ffff88810f8bda78 object type: timer_list hint: br_ip6_multicast_port_query_expired (net/bridge/br_multicast.c:1927)\nWARNING: lib/debugobjects.c:629 at debug_print_object+0x1b1/0x3e0, CPU#5: swapper/5/0\n[...]\nCall Trace:\n<IRQ>\n__debug_check_no_obj_freed (lib/debugobjects.c:1116)\nkfree (mm/slub.c:2620 mm/slub.c:6250 mm/slub.c:6565)\nkobject_cleanup (lib/kobject.c:689)\nrcu_do_batch (kernel/rcu/tree.c:2617)\nrcu_core (kernel/rcu/tree.c:2869)\nhandle_softirqs (kernel/softirq.c:622)\n__irq_exit_rcu (kernel/softirq.c:656 kernel/softirq.c:496 kernel/softirq.c:735)\nirq_exit_rcu (kernel/softirq.c:752)\nsysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1061 (discriminator 47) arch/x86/kernel/apic/apic.c:1061 (discriminator 47))\n</IRQ>"}], "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 code is reached only through local bridge administration (rtnetlink RTM_NEWLINK, bridge ioctl, or sysfs), not through processing of remote network packets. An attacker must issue `ip link`/`bridge` configuration commands to create the inconsistent multicast state and remove a bridge port.\nAC:L - The reproducer sequence is fully attacker-controlled and deterministic; syzkaller triggered it reliably. The attacker configures the toggle sequence, removes the port, and the orphaned IGMP/MLD query timers fire on schedule without depending on uncontrollable timing or memory layout.\nPR:L - All entry paths require CAP_NET_ADMIN in the target network namespace (rtnetlink at rtnl_newlink, br_ioctl add_del_if, sysfs bridge attributes). Unprivileged local users can obtain this capability by creating a user+network namespace (`unshare -Urn`), which is widely enabled on server and container hosts.\nUI:N - Exploitation requires no action from any other user or victim; the attacker performs the entire bridge setup, state toggling, and port removal themselves.\nS:U - Successful exploitation corrupts kernel memory within the same kernel security domain. This is a standard local kernel memory corruption issue, not a cross-boundary escape such as VM guest-to-host or IOMMU bypass.\nC:H - This is a heap use-after-free on a freed net_bridge_port structure; the timer callback dereferences pmctx->port->br on freed memory. UAF on kernel slab objects enables arbitrary kernel memory reads via heap grooming and reclamation of the freed port object.\nI:H - The UAF occurs in a timer softirq handler that reads and writes through fields of the freed port multicast context, including sending queries via br_multicast_send_query. Kernel heap UAF is exploitable for arbitrary write and control-flow hijack primitives, not merely a crash.\nA:H - The freed port structure is kfree'd while IGMP/MLD own-query timers remain active, producing a debugobjects \"free active timer\" warning and use-after-free in softirq. This reliably causes kernel oops/panic and can be triggered repeatedly to deny service on shared infrastructure such as cloud hosts or software switches."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/bridge/br_multicast.c"], "versions": [{"version": "410a033bfa8c7daefbae0225c836693db2149ec1", "lessThan": "ddefd1b8e5eb58933a697ab38334f0fd82e7fb8b", "status": "affected", "versionType": "git"}, {"version": "c6d16eab122744df698f18b47cf771945cd55066", "lessThan": "ed3b69e60385a03df11c6d12e5d7bdf0f4a11b70", "status": "affected", "versionType": "git"}, {"version": "b4c83b37490d61cfdd62a2b29e98a9b89004b5c0", "lessThan": "1900ca8acb92fbea8bf9abef9927c7fed03db7fc", "status": "affected", "versionType": "git"}, {"version": "78f768e36c065ca3f88272fcf39014782c2d4ecd", "lessThan": "ebe5561154c823b323bd06e350b55e0b8604d851", "status": "affected", "versionType": "git"}, {"version": "4b30ae9adb047dd0a7982975ec3933c529537026", "lessThan": "a9224862d597d0eed0a34bbb27343f703fc4113f", "status": "affected", "versionType": "git"}, {"version": "4b30ae9adb047dd0a7982975ec3933c529537026", "lessThan": "7213256c91ed778a0997c2029c152b18dc50e4fd", "status": "affected", "versionType": "git"}, {"version": "4b30ae9adb047dd0a7982975ec3933c529537026", "lessThan": "4df78ff02629c7729168f0696a7a2123c389818d", "status": "affected", "versionType": "git"}, {"version": "c996e25df0b3282c724bb5aca434518bc08cd963", "status": "affected", "versionType": "git"}, {"version": "5.15.186", "lessThan": "5.15.209", "status": "affected", "versionType": "semver"}, {"version": "6.1.142", "lessThan": "6.1.175", "status": "affected", "versionType": "semver"}, {"version": "6.6.95", "lessThan": "6.6.142", "status": "affected", "versionType": "semver"}, {"version": "6.12.35", "lessThan": "6.12.92", "status": "affected", "versionType": "semver"}, {"version": "6.15.4", "lessThan": "6.16", 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{"version": "7.1", "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": "5.15.186", "versionEndExcluding": "5.15.209"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.142", "versionEndExcluding": "6.1.175"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.95", "versionEndExcluding": "6.6.142"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.35", "versionEndExcluding": "6.12.92"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "6.18.34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "7.0.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "7.1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15.4"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/ddefd1b8e5eb58933a697ab38334f0fd82e7fb8b"}, {"url": "https://git.kernel.org/stable/c/ed3b69e60385a03df11c6d12e5d7bdf0f4a11b70"}, {"url": "https://git.kernel.org/stable/c/1900ca8acb92fbea8bf9abef9927c7fed03db7fc"}, {"url": "https://git.kernel.org/stable/c/ebe5561154c823b323bd06e350b55e0b8604d851"}, {"url": "https://git.kernel.org/stable/c/a9224862d597d0eed0a34bbb27343f703fc4113f"}, {"url": "https://git.kernel.org/stable/c/7213256c91ed778a0997c2029c152b18dc50e4fd"}, {"url": "https://git.kernel.org/stable/c/4df78ff02629c7729168f0696a7a2123c389818d"}], "title": "bridge: mcast: Fix a possible use-after-free when removing a bridge port", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-64032", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:35:39.604315Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-416", "description": "CWE-416 Use After Free"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-19T20:28:09.740Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-64032", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:35:39.604315Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T15:35:40.411Z"}}], "cna": {"title": "bridge: mcast: Fix a possible use-after-free when removing a bridge port", "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 vulnerable code is reached only through local bridge administration (rtnetlink RTM_NEWLINK, bridge ioctl, or sysfs), not through processing of remote network packets. An attacker must issue `ip link`/`bridge` configuration commands to create the inconsistent multicast state and remove a bridge port.\nAC:L - The reproducer sequence is fully attacker-controlled and deterministic; syzkaller triggered it reliably. The attacker configures the toggle sequence, removes the port, and the orphaned IGMP/MLD query timers fire on schedule without depending on uncontrollable timing or memory layout.\nPR:L - All entry paths require CAP_NET_ADMIN in the target network namespace (rtnetlink at rtnl_newlink, br_ioctl add_del_if, sysfs bridge attributes). Unprivileged local users can obtain this capability by creating a user+network namespace (`unshare -Urn`), which is widely enabled on server and container hosts.\nUI:N - Exploitation requires no action from any other user or victim; the attacker performs the entire bridge setup, state toggling, and port removal themselves.\nS:U - Successful exploitation corrupts kernel memory within the same kernel security domain. This is a standard local kernel memory corruption issue, not a cross-boundary escape such as VM guest-to-host or IOMMU bypass.\nC:H - This is a heap use-after-free on a freed net_bridge_port structure; the timer callback dereferences pmctx->port->br on freed memory. UAF on kernel slab objects enables arbitrary kernel memory reads via heap grooming and reclamation of the freed port object.\nI:H - The UAF occurs in a timer softirq handler that reads and writes through fields of the freed port multicast context, including sending queries via br_multicast_send_query. Kernel heap UAF is exploitable for arbitrary write and control-flow hijack primitives, not merely a crash.\nA:H - The freed port structure is kfree'd while IGMP/MLD own-query timers remain active, producing a debugobjects \"free active timer\" warning and use-after-free in softirq. This reliably causes kernel oops/panic and can be triggered repeatedly to deny service on shared infrastructure such as cloud hosts or software switches."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "410a033bfa8c7daefbae0225c836693db2149ec1", "lessThan": "ddefd1b8e5eb58933a697ab38334f0fd82e7fb8b", "versionType": "git"}, {"status": "affected", "version": "c6d16eab122744df698f18b47cf771945cd55066", "lessThan": "ed3b69e60385a03df11c6d12e5d7bdf0f4a11b70", "versionType": "git"}, {"status": "affected", "version": "b4c83b37490d61cfdd62a2b29e98a9b89004b5c0", "lessThan": "1900ca8acb92fbea8bf9abef9927c7fed03db7fc", "versionType": "git"}, {"status": "affected", "version": "78f768e36c065ca3f88272fcf39014782c2d4ecd", "lessThan": "ebe5561154c823b323bd06e350b55e0b8604d851", "versionType": "git"}, {"status": "affected", "version": "4b30ae9adb047dd0a7982975ec3933c529537026", "lessThan": "a9224862d597d0eed0a34bbb27343f703fc4113f", "versionType": "git"}, {"status": "affected", "version": "4b30ae9adb047dd0a7982975ec3933c529537026", "lessThan": "7213256c91ed778a0997c2029c152b18dc50e4fd", "versionType": "git"}, {"status": "affected", "version": "4b30ae9adb047dd0a7982975ec3933c529537026", "lessThan": "4df78ff02629c7729168f0696a7a2123c389818d", "versionType": "git"}, {"status": "affected", "version": "c996e25df0b3282c724bb5aca434518bc08cd963", "versionType": "git"}, {"status": "affected", "version": "5.15.186", "lessThan": "5.15.209", "versionType": "semver"}, {"status": "affected", "version": "6.1.142", "lessThan": "6.1.175", "versionType": "semver"}, {"status": "affected", "version": "6.6.95", "lessThan": "6.6.142", "versionType": "semver"}, {"status": "affected", "version": "6.12.35", "lessThan": "6.12.92", "versionType": "semver"}, {"status": "affected", "version": "6.15.4", "lessThan": "6.16", "versionType": "semver"}], "programFiles": ["net/bridge/br_multicast.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.16"}, {"status": "unaffected", "version": "0", "lessThan": "6.16", "versionType": "semver"}, {"status": "unaffected", "version": "5.15.209", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.175", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.142", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.92", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.34", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.11", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/bridge/br_multicast.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/ddefd1b8e5eb58933a697ab38334f0fd82e7fb8b"}, {"url": "https://git.kernel.org/stable/c/ed3b69e60385a03df11c6d12e5d7bdf0f4a11b70"}, {"url": "https://git.kernel.org/stable/c/1900ca8acb92fbea8bf9abef9927c7fed03db7fc"}, {"url": "https://git.kernel.org/stable/c/ebe5561154c823b323bd06e350b55e0b8604d851"}, {"url": "https://git.kernel.org/stable/c/a9224862d597d0eed0a34bbb27343f703fc4113f"}, {"url": "https://git.kernel.org/stable/c/7213256c91ed778a0997c2029c152b18dc50e4fd"}, {"url": "https://git.kernel.org/stable/c/4df78ff02629c7729168f0696a7a2123c389818d"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: mcast: Fix a possible use-after-free when removing a bridge port\n\nWhen per-VLAN multicast snooping is enabled, the bridge iterates over\nall the bridge ports, disables the per-port multicast context on each\nport and enables the per-{port, VLAN} multicast contexts instead. The\nreverse happens when per-VLAN multicast snooping is disabled.\n\nWhen global multicast snooping is enabled, the bridge iterates over all\nthe bridge ports and enables the per-port multicast context on each\nport. The reverse happens when multicast snooping is disabled.\n\nThe above scheme can result in a situation where both types of contexts\n(per-port and per-{port, VLAN}) are enabled on a single bridge port:\n\n # ip link add name br1 up type bridge mcast_snooping 1 mcast_querier 1 vlan_filtering 1\n # ip link add name dummy1 up master br1 type dummy\n # ip link set dev br1 type bridge mcast_vlan_snooping 1\n # ip link set dev br1 type bridge mcast_snooping 0\n # ip link set dev br1 type bridge mcast_snooping 1\n\nThis is not intended and it is a problem since the commit cited below.\nPrior to this commit, when removing a bridge port,\nbr_multicast_disable_port() would disable the per-port multicast context\nand the per-{port, VLAN} multicast contexts would get disabled when\nflushing VLANs.\n\nAfter this commit, br_multicast_disable_port() only disables the\nper-port multicast context if per-VLAN multicast snooping is disabled.\nIf both types of contexts were enabled on the port when it was removed,\nthe per-port multicast context would remain enabled when freeing the\nbridge port, leading to a use-after-free [1].\n\nFix by preventing the bridge from enabling / disabling the per-port\nmulticast contexts when toggling global multicast snooping if per-VLAN\nmulticast snooping is enabled.\n\n[1]\nODEBUG: free active (active state 0) object: ffff88810f8bda78 object type: timer_list hint: br_ip6_multicast_port_query_expired (net/bridge/br_multicast.c:1927)\nWARNING: lib/debugobjects.c:629 at debug_print_object+0x1b1/0x3e0, CPU#5: swapper/5/0\n[...]\nCall Trace:\n<IRQ>\n__debug_check_no_obj_freed (lib/debugobjects.c:1116)\nkfree (mm/slub.c:2620 mm/slub.c:6250 mm/slub.c:6565)\nkobject_cleanup (lib/kobject.c:689)\nrcu_do_batch (kernel/rcu/tree.c:2617)\nrcu_core (kernel/rcu/tree.c:2869)\nhandle_softirqs (kernel/softirq.c:622)\n__irq_exit_rcu (kernel/softirq.c:656 kernel/softirq.c:496 kernel/softirq.c:735)\nirq_exit_rcu (kernel/softirq.c:752)\nsysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1061 (discriminator 47) arch/x86/kernel/apic/apic.c:1061 (discriminator 47))\n</IRQ>"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.209", "versionStartIncluding": "5.15.186"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.175", "versionStartIncluding": "6.1.142"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.142", "versionStartIncluding": "6.6.95"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.92", "versionStartIncluding": "6.12.35"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.34", "versionStartIncluding": "6.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.0.11", "versionStartIncluding": "6.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1", "versionStartIncluding": "6.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionStartIncluding": "6.15.4"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:38:26.376Z"}}}, "cveMetadata": {"cveId": "CVE-2026-64032", "state": "PUBLISHED", "dateUpdated": "2026-10-16T15:42:19.942Z", "dateReserved": "2026-07-19T07:54:57.028Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-07-19T15:39:22.228Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

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"versionType": "git"}, {"lessThan": "7213256c91ed778a0997c2029c152b18dc50e4fd", "status": "affected", "version": "4b30ae9adb047dd0a7982975ec3933c529537026", "versionType": "git"}, {"lessThan": "4df78ff02629c7729168f0696a7a2123c389818d", "status": "affected", "version": "4b30ae9adb047dd0a7982975ec3933c529537026", "versionType": "git"}, {"status": "affected", "version": "c996e25df0b3282c724bb5aca434518bc08cd963", "versionType": "git"}, {"lessThan": "5.15.209", "status": "affected", "version": "5.15.186", "versionType": "semver"}, {"lessThan": "6.1.175", "status": "affected", "version": "6.1.142", "versionType": "semver"}, {"lessThan": "6.6.142", "status": "affected", "version": "6.6.95", "versionType": "semver"}, {"lessThan": "6.12.92", "status": "affected", "version": "6.12.35", "versionType": "semver"}, {"lessThan": "6.16", "status": "affected", "version": "6.15.4", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/bridge/br_multicast.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.16"}, {"lessThan": "6.16", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.209", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.175", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.142", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.92", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.34", "versionType": "semver"}, {"lessThanOrEqual": "7.0.*", "status": "unaffected", "version": "7.0.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "D08BD58F-58F3-4451-BE7A-23A12841D537", "versionEndExcluding": "5.15.209", "versionStartIncluding": "5.15.186", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "D5FC7F85-DD01-4DCE-B60F-B05FE77BCF15", "versionEndExcluding": "6.1.175", "versionStartIncluding": "6.1.142", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "0C7C9398-4190-4C40-944F-78C764865915", "versionEndExcluding": "6.6.142", "versionStartIncluding": "6.6.95", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "70782DE8-5182-47E8-8C25-788A7ED11DD6", "versionEndExcluding": "6.12.92", "versionStartIncluding": "6.12.35", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "3AD638FE-824A-419C-AEB8-E57F01A1F4FC", "versionEndExcluding": "6.18.34", "versionStartIncluding": "6.15.4", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "0520D091-FC52-4A50-AF07-70AE7D08B750", "versionEndExcluding": "7.0.11", "versionStartIncluding": "6.19", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*", "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*", "matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*", "matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: mcast: Fix a possible use-after-free when removing a bridge port\n\nWhen per-VLAN multicast snooping is enabled, the bridge iterates over\nall the bridge ports, disables the per-port multicast context on each\nport and enables the per-{port, VLAN} multicast contexts instead. The\nreverse happens when per-VLAN multicast snooping is disabled.\n\nWhen global multicast snooping is enabled, the bridge iterates over all\nthe bridge ports and enables the per-port multicast context on each\nport. The reverse happens when multicast snooping is disabled.\n\nThe above scheme can result in a situation where both types of contexts\n(per-port and per-{port, VLAN}) are enabled on a single bridge port:\n\n # ip link add name br1 up type bridge mcast_snooping 1 mcast_querier 1 vlan_filtering 1\n # ip link add name dummy1 up master br1 type dummy\n # ip link set dev br1 type bridge mcast_vlan_snooping 1\n # ip link set dev br1 type bridge mcast_snooping 0\n # ip link set dev br1 type bridge mcast_snooping 1\n\nThis is not intended and it is a problem since the commit cited below.\nPrior to this commit, when removing a bridge port,\nbr_multicast_disable_port() would disable the per-port multicast context\nand the per-{port, VLAN} multicast contexts would get disabled when\nflushing VLANs.\n\nAfter this commit, br_multicast_disable_port() only disables the\nper-port multicast context if per-VLAN multicast snooping is disabled.\nIf both types of contexts were enabled on the port when it was removed,\nthe per-port multicast context would remain enabled when freeing the\nbridge port, leading to a use-after-free [1].\n\nFix by preventing the bridge from enabling / disabling the per-port\nmulticast contexts when toggling global multicast snooping if per-VLAN\nmulticast snooping is enabled.\n\n[1]\nODEBUG: free active (active state 0) object: ffff88810f8bda78 object type: timer_list hint: br_ip6_multicast_port_query_expired (net/bridge/br_multicast.c:1927)\nWARNING: lib/debugobjects.c:629 at debug_print_object+0x1b1/0x3e0, CPU#5: swapper/5/0\n[...]\nCall Trace:\n<IRQ>\n__debug_check_no_obj_freed (lib/debugobjects.c:1116)\nkfree (mm/slub.c:2620 mm/slub.c:6250 mm/slub.c:6565)\nkobject_cleanup (lib/kobject.c:689)\nrcu_do_batch (kernel/rcu/tree.c:2617)\nrcu_core (kernel/rcu/tree.c:2869)\nhandle_softirqs (kernel/softirq.c:622)\n__irq_exit_rcu (kernel/softirq.c:656 kernel/softirq.c:496 kernel/softirq.c:735)\nirq_exit_rcu (kernel/softirq.c:752)\nsysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1061 (discriminator 47) arch/x86/kernel/apic/apic.c:1061 (discriminator 47))\n</IRQ>"}], "id": "CVE-2026-64032", "lastModified": "2026-10-19T21:17:20.740", "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-2026-64032", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:35:39.604315Z", "version": "2.0.3"}}]}, "published": "2026-07-19T16:17:43.350", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/1900ca8acb92fbea8bf9abef9927c7fed03db7fc"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4df78ff02629c7729168f0696a7a2123c389818d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7213256c91ed778a0997c2029c152b18dc50e4fd"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a9224862d597d0eed0a34bbb27343f703fc4113f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/ddefd1b8e5eb58933a697ab38334f0fd82e7fb8b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/ebe5561154c823b323bd06e350b55e0b8604d851"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/ed3b69e60385a03df11c6d12e5d7bdf0f4a11b70"}], "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: bridge: mcast: Fix a possible use-after-free when removing a bridge port", "id": "2502332", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2502332"}, "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-825", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbridge: mcast: Fix a possible use-after-free when removing a bridge port\nWhen per-VLAN multicast snooping is enabled, the bridge iterates over\nall the bridge ports, disables the per-port multicast context on each\nport and enables the per-{port, VLAN} multicast contexts instead. The\nreverse happens when per-VLAN multicast snooping is disabled.\nWhen global multicast snooping is enabled, the bridge iterates over all\nthe bridge ports and enables the per-port multicast context on each\nport. The reverse happens when multicast snooping is disabled.\nThe above scheme can result in a situation where both types of contexts\n(per-port and per-{port, VLAN}) are enabled on a single bridge port:\n# ip link add name br1 up type bridge mcast_snooping 1 mcast_querier 1 vlan_filtering 1\n# ip link add name dummy1 up master br1 type dummy\n# ip link set dev br1 type bridge mcast_vlan_snooping 1\n# ip link set dev br1 type bridge mcast_snooping 0\n# ip link set dev br1 type bridge mcast_snooping 1\nThis is not intended and it is a problem since the commit cited below.\nPrior to this commit, when removing a bridge port,\nbr_multicast_disable_port() would disable the per-port multicast context\nand the per-{port, VLAN} multicast contexts would get disabled when\nflushing VLANs.\nAfter this commit, br_multicast_disable_port() only disables the\nper-port multicast context if per-VLAN multicast snooping is disabled.\nIf both types of contexts were enabled on the port when it was removed,\nthe per-port multicast context would remain enabled when freeing the\nbridge port, leading to a use-after-free [1].\nFix by preventing the bridge from enabling / disabling the per-port\nmulticast contexts when toggling global multicast snooping if per-VLAN\nmulticast snooping is enabled.\n[1]\nODEBUG: free active (active state 0) object: ffff88810f8bda78 object type: timer_list hint: br_ip6_multicast_port_query_expired (net/bridge/br_multicast.c:1927)\nWARNING: lib/debugobjects.c:629 at debug_print_object+0x1b1/0x3e0, CPU#5: swapper/5/0\n[...]\nCall Trace:\n<IRQ>\n__debug_check_no_obj_freed (lib/debugobjects.c:1116)\nkfree (mm/slub.c:2620 mm/slub.c:6250 mm/slub.c:6565)\nkobject_cleanup (lib/kobject.c:689)\nrcu_do_batch (kernel/rcu/tree.c:2617)\nrcu_core (kernel/rcu/tree.c:2869)\nhandle_softirqs (kernel/softirq.c:622)\n__irq_exit_rcu (kernel/softirq.c:656 kernel/softirq.c:496 kernel/softirq.c:735)\nirq_exit_rcu (kernel/softirq.c:752)\nsysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1061 (discriminator 47) arch/x86/kernel/apic/apic.c:1061 (discriminator 47))\n</IRQ>", "A flaw was found in the Linux kernel's bridge multicast functionality. Improper management of multicast contexts when a bridge port is removed can lead to a use-after-free vulnerability. This issue could allow a local attacker to cause a system crash, resulting in a denial of service."], "name": "CVE-2026-64032", "public_date": "2026-07-19T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64032\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64032\nhttps://lore.kernel.org/linux-cve-announce/2026071904-CVE-2026-64032-9dca@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[410a033bfa8c7daefbae0225c836693db2149ec1,ddefd1b8e5eb58933a697ab38334f0fd82e7fb8b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[c6d16eab122744df698f18b47cf771945cd55066,ed3b69e60385a03df11c6d12e5d7bdf0f4a11b70)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[b4c83b37490d61cfdd62a2b29e98a9b89004b5c0,1900ca8acb92fbea8bf9abef9927c7fed03db7fc)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[78f768e36c065ca3f88272fcf39014782c2d4ecd,ebe5561154c823b323bd06e350b55e0b8604d851)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b30ae9adb047dd0a7982975ec3933c529537026,a9224862d597d0eed0a34bbb27343f703fc4113f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b30ae9adb047dd0a7982975ec3933c529537026,7213256c91ed778a0997c2029c152b18dc50e4fd)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b30ae9adb047dd0a7982975ec3933c529537026,4df78ff02629c7729168f0696a7a2123c389818d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "c996e25df0b3282c724bb5aca434518bc08cd963"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[5.15.186,5.15.209)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.1.142,6.1.175)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.6.95,6.6.142)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.12.35,6.12.92)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.15.4,6.16)"}}], "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": "6.16"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.16)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[5.15.209,5.15.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.1.175,6.1.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.6.142,6.6.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.12.92,6.12.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.34,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.0.11,7.0.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1,*]"}}], "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": "2026-07-21T22:30:05.613925+00:00", "updated": "2026-10-17T09:45:06.192479+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}