{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74398", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.891Z", "datePublished": "2026-08-15T05:59:10.113Z", "dateUpdated": "2026-08-17T05:46:43.132Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:46:43.132Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD\n\naddrconf_dad_failure() transitions ifp->state from DAD to POSTDAD\nvia addrconf_dad_end(), which drops ifp->lock on return. The lock\nis re-acquired after net_info_ratelimited(). A concurrent\nipv6_del_addr() can take the lock in that window, set ifp->state\nto DEAD and run list_del_rcu(&ifp->if_list).\n\naddrconf_dad_failure() then overwrites DEAD with ERRDAD at errdad:\nand schedules a new dad_work. The work calls ipv6_del_addr()\nagain, hitting the already-poisoned list entry:\n\n general protection fault: 0000 [#1] SMP NOPTI\n CPU: 4 PID: 217 Comm: kworker/4:1\n Workqueue: ipv6_addrconf addrconf_dad_work\n RIP: 0010:ipv6_del_addr+0xe9/0x280\n RAX: dead000000000122\n Call Trace:\n addrconf_dad_stop+0x113/0x140\n addrconf_dad_work+0x28c/0x430\n process_one_work+0x1eb/0x3b0\n worker_thread+0x4d/0x400\n kthread+0x104/0x140\n ret_from_fork+0x35/0x40\n\nFold the addrconf_dad_end() logic into addrconf_dad_failure() under\na single ifp->lock critical section. The STABLE_PRIVACY branch\ntemporarily drops ifp->lock around address regeneration, so at\nlock_errdad: verify the state is still POSTDAD before transitioning\nto ERRDAD; bail out otherwise to avoid overwriting a state set by\nanother path while the lock was released." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The bug is reached from inbound ICMPv6 Neighbor Discovery (NS/NA) packets processed by icmp6_rcv()→ndisc_rcv()→addrconf_dad_failure(), the standard IPv6 network receive path on internet-facing servers, cloud VMs, phones, and IoT devices on shared L2 segments.\nAC:L - An attacker controls both sides of the race by flooding forged NS/NA during DAD while concurrently triggering ipv6_del_addr() via RTM_DELADDR/CAP_NET_ADMIN in a user namespace, CNI/orchestration address teardown, or interface-down processing; retries make the narrow window reliably winnable.\nPR:N - Triggering DAD failure requires only unauthenticated ND packet injection on the victim's link; the concurrent ipv6_del_addr() leg needs no victim credentials and can come from automatic address lifecycle events (CNI churn, SLAAC/privacy regeneration, netdev down) rather than attacker admin rights.\nUI:N - Exploitation does not require any victim user action such as opening files or mounting filesystems; it targets automatic IPv6 address configuration and DAD processing that occurs during normal network connectivity and boot.\nS:U - The corrupted inet6_ifaddr lifecycle and resulting kernel crash occur within kernel memory management; impact does not cross a VM, container, or IOMMU security boundary into a separate authority.\nC:H - The race leaves a freed/partially torn-down inet6_ifaddr with corrupted state and a poisoned RCU list entry (LIST_POISON2), constituting use-after-free class memory corruption that can expose adjacent kernel heap contents beyond a pure crash.\nI:H - Corrupting inet6_ifaddr state after list_del_rcu() and re-queuing dad_work on a dead object enables heap reuse and control of freed object contents, providing a path to arbitrary kernel memory writes and potential code execution beyond denial of service.\nA:H - The demonstrated failure is a general protection fault in ipv6_del_addr() from addrconf_dad_work on the ipv6_addrconf workqueue, causing a kernel oops/panic and complete loss of system availability on affected hosts." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/addrconf.c" ], "versions": [ { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "47b05836705b63dab93d9ac7c69a3a507375ef80", "status": "affected", "versionType": "git" }, { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "d21be7d051012c6b572fa4e3334443c250216f7b", "status": "affected", "versionType": "git" }, { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "875c284c0f98b042bb97abad460f63a24c977f88", "status": "affected", "versionType": "git" }, { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "8ed0ce9ea58d677d1bac92614ee5f60f8ea57363", "status": "affected", "versionType": "git" }, { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "3bdc86d89fd6c6523753fa6f42fcfaf30ee699cb", "status": "affected", "versionType": "git" }, { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "b61af0268e3d1308c466bf0be5dced844eafc1ef", "status": "affected", "versionType": "git" }, { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "e889aa99ad3ed48bb0ddcff6475b17542532d18b", "status": "affected", "versionType": "git" }, { "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51", "lessThan": "627ac78f2741e2ebd2225e2e953b6964a8a9182f", "status": "affected", "versionType": "git" }, { "version": "835b474b8f70fa68d68abffad37378e92f661802", "status": "affected", "versionType": "git" }, { "version": "3.10.105", "lessThan": "3.11", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/addrconf.c" ], "versions": [ { "version": "3.14", "status": "affected" }, { "version": "0", "lessThan": "3.14", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.261", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.212", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "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": "3.14", "versionEndExcluding": "5.10.261" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "5.15.212" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "7.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10.105" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/47b05836705b63dab93d9ac7c69a3a507375ef80" }, { "url": "https://git.kernel.org/stable/c/d21be7d051012c6b572fa4e3334443c250216f7b" }, { "url": "https://git.kernel.org/stable/c/875c284c0f98b042bb97abad460f63a24c977f88" }, { "url": "https://git.kernel.org/stable/c/8ed0ce9ea58d677d1bac92614ee5f60f8ea57363" }, { "url": "https://git.kernel.org/stable/c/3bdc86d89fd6c6523753fa6f42fcfaf30ee699cb" }, { "url": "https://git.kernel.org/stable/c/b61af0268e3d1308c466bf0be5dced844eafc1ef" }, { "url": "https://git.kernel.org/stable/c/e889aa99ad3ed48bb0ddcff6475b17542532d18b" }, { "url": "https://git.kernel.org/stable/c/627ac78f2741e2ebd2225e2e953b6964a8a9182f" } ], "title": "ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD", "x_generator": { "engine": "bippy-1.2.0" } } } }