{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-31406", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.086Z", "datePublished": "2026-04-06T07:38:18.840Z", "dateUpdated": "2026-04-06T07:38:18.840Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-04-06T07:38:18.840Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()\n\nAfter cancel_delayed_work_sync() is called from\nxfrm_nat_keepalive_net_fini(), xfrm_state_fini() flushes remaining\nstates via __xfrm_state_delete(), which calls\nxfrm_nat_keepalive_state_updated() to re-schedule nat_keepalive_work.\n\nThe following is a simple race scenario:\n\n cpu0 cpu1\n\ncleanup_net() [Round 1]\n ops_undo_list()\n xfrm_net_exit()\n xfrm_nat_keepalive_net_fini()\n cancel_delayed_work_sync(nat_keepalive_work);\n xfrm_state_fini()\n xfrm_state_flush()\n xfrm_state_delete(x)\n __xfrm_state_delete(x)\n xfrm_nat_keepalive_state_updated(x)\n schedule_delayed_work(nat_keepalive_work);\n rcu_barrier();\n net_complete_free();\n net_passive_dec(net);\n llist_add(&net->defer_free_list, &defer_free_list);\n\ncleanup_net() [Round 2]\n rcu_barrier();\n net_complete_free()\n kmem_cache_free(net_cachep, net);\n nat_keepalive_work()\n // on freed net\n\nTo prevent this, cancel_delayed_work_sync() is replaced with\ndisable_delayed_work_sync()."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/xfrm/xfrm_nat_keepalive.c"], "versions": [{"version": "f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae", "lessThan": "32d0f44c2f14d60fe8e920e69a28c11051543ec1", "status": "affected", "versionType": "git"}, {"version": "f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae", "lessThan": "2255ed6adbc3100d2c4a83abd9d0396d04b87792", "status": "affected", "versionType": "git"}, {"version": "f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae", "lessThan": "21f2fc49ca6faa393c31da33b8a4e6c41fc84c13", "status": "affected", "versionType": "git"}, {"version": "f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae", "lessThan": "daf8e3b253aa760ff9e96c7768a464bc1d6b3c90", "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/xfrm/xfrm_nat_keepalive.c"], "versions": [{"version": "6.11", "status": "affected"}, {"version": "0", "lessThan": "6.11", "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-rc6", "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": "6.11", "versionEndExcluding": "6.12.80"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.18.21"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.19.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "7.0-rc6"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/32d0f44c2f14d60fe8e920e69a28c11051543ec1"}, {"url": "https://git.kernel.org/stable/c/2255ed6adbc3100d2c4a83abd9d0396d04b87792"}, {"url": "https://git.kernel.org/stable/c/21f2fc49ca6faa393c31da33b8a4e6c41fc84c13"}, {"url": "https://git.kernel.org/stable/c/daf8e3b253aa760ff9e96c7768a464bc1d6b3c90"}], "title": "xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()\n\nAfter cancel_delayed_work_sync() is called from\nxfrm_nat_keepalive_net_fini(), xfrm_state_fini() flushes remaining\nstates via __xfrm_state_delete(), which calls\nxfrm_nat_keepalive_state_updated() to re-schedule nat_keepalive_work.\n\nThe following is a simple race scenario:\n\n cpu0 cpu1\n\ncleanup_net() [Round 1]\n ops_undo_list()\n xfrm_net_exit()\n xfrm_nat_keepalive_net_fini()\n cancel_delayed_work_sync(nat_keepalive_work);\n xfrm_state_fini()\n xfrm_state_flush()\n xfrm_state_delete(x)\n __xfrm_state_delete(x)\n xfrm_nat_keepalive_state_updated(x)\n schedule_delayed_work(nat_keepalive_work);\n rcu_barrier();\n net_complete_free();\n net_passive_dec(net);\n llist_add(&net->defer_free_list, &defer_free_list);\n\ncleanup_net() [Round 2]\n rcu_barrier();\n net_complete_free()\n kmem_cache_free(net_cachep, net);\n nat_keepalive_work()\n // on freed net\n\nTo prevent this, cancel_delayed_work_sync() is replaced with\ndisable_delayed_work_sync()."}], "id": "CVE-2026-31406", "lastModified": "2026-04-07T13:20:35.010", "metrics": {}, "published": "2026-04-06T08:16:38.457", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/21f2fc49ca6faa393c31da33b8a4e6c41fc84c13"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/2255ed6adbc3100d2c4a83abd9d0396d04b87792"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/32d0f44c2f14d60fe8e920e69a28c11051543ec1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/daf8e3b253aa760ff9e96c7768a464bc1d6b3c90"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{"bugzilla": {"description": "kernel: xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()", "id": "2455332", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2455332"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in the Linux kernel, specifically within its xfrm (IP eXtensible FRamework) component. This vulnerability arises from a race condition during network cleanup, where a scheduled task (nat_keepalive_work) can be re-activated and attempt to operate on memory that has already been freed. This 'use-after-free' condition could allow a local attacker to cause the system to crash, leading to a denial of service, or potentially execute unauthorized code."], "name": "CVE-2026-31406", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-04-06T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31406\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31406\nhttps://lore.kernel.org/linux-cve-announce/2026040628-CVE-2026-31406-e2f3@gregkh/T"], "statement": "After `cancel_delayed_work_sync()` in `xfrm_nat_keepalive_net_fini()`, state deletion could reschedule `nat_keepalive_work` on a net being torn down. Replacing with `disable_delayed_work_sync()` prevents new schedules. Trigger is network namespace teardown with xfrm NAT keepalive in use.", "threat_severity": "Moderate"}