{"cve":"CVE-2026-74398","nvd":{"published":"2026-08-15T06:22:41.790","modified":"2026-10-16T20:17:25.390","status":"Received","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":[],"references":["https://git.kernel.org/stable/c/3bdc86d89fd6c6523753fa6f42fcfaf30ee699cb","https://git.kernel.org/stable/c/47b05836705b63dab93d9ac7c69a3a507375ef80","https://git.kernel.org/stable/c/627ac78f2741e2ebd2225e2e953b6964a8a9182f","https://git.kernel.org/stable/c/875c284c0f98b042bb97abad460f63a24c977f88","https://git.kernel.org/stable/c/8ed0ce9ea58d677d1bac92614ee5f60f8ea57363"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:10.689564601+00:00"},"epss":{"cve":"CVE-2026-74398","score":0.00514,"percentile":0.43523,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}