{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-53239", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.393Z", "datePublished": "2026-06-25T08:39:35.149Z", "dateUpdated": "2026-08-05T12:34:25.656Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:34:25.656Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx()\n\nFix the race by pruning the bin while still holding xfrm_policy_lock,\nbefore dropping it. Use __xfrm_policy_inexact_prune_bin() directly since\nthe lock is already held. The wrapper xfrm_policy_inexact_prune_bin()\nbecomes unused and is removed.\n\nRace:\n\n CPU0 (XFRM_MSG_DELPOLICY) CPU1 (XFRM_MSG_NEWSPDINFO)\n ========================== ==========================\n xfrm_policy_bysel_ctx():\n spin_lock_bh(xfrm_policy_lock)\n bin = xfrm_policy_inexact_lookup()\n __xfrm_policy_unlink(pol)\n spin_unlock_bh(xfrm_policy_lock)\n xfrm_policy_kill(ret)\n // wide window, lock not held\n xfrm_hash_rebuild():\n spin_lock_bh(xfrm_policy_lock)\n __xfrm_policy_inexact_flush():\n kfree_rcu(bin) // bin freed\n spin_unlock_bh(xfrm_policy_lock)\n xfrm_policy_inexact_prune_bin(bin)\n // UAF: bin is freed" } ], "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 path is reached through NETLINK_XFRM messages such as XFRM_MSG_DELPOLICY and XFRM_MSG_NEWSPDINFO, which require local netlink access rather than remote packet delivery.\nAC:L - The attacker controls both sides of the race by creating/deleting an inexact XFRM policy while concurrently triggering SPD hash rebuilds, with no required external victim state.\nPR:L - XFRM netlink operations require CAP_NET_ADMIN, but the check is namespace-scoped via netlink_net_capable() and is reachable with CAP_NET_ADMIN in a user-created network namespace on systems allowing user namespaces.\nUI:N - No victim action is required; the attacker can issue the needed netlink messages directly.\nS:U - The vulnerability corrupts kernel networking/XFRM state within the same kernel security authority and does not cross a hypervisor, IOMMU, or separate trust boundary.\nC:H - This is a use-after-free of an XFRM inexact policy bin, and the stale freed object can be dereferenced after attacker-controlled heap reuse, making high confidentiality impact defensible.\nI:H - The stale bin is not only read but also passed into pruning logic that writes list/rhashtable/seqcount state, so exploitation can plausibly yield memory corruption and control-flow or data integrity compromise.\nA:H - The UAF can trigger kernel memory corruption, KASAN splats, oopses, or panics, giving high availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/xfrm/xfrm_policy.c" ], "versions": [ { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "8fc536e9f6856230f19c7d13e71af064b6a77b22", "status": "affected", "versionType": "git" }, { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "c4c1ea36d83bf3c4569468ca5b8b614fda1bf821", "status": "affected", "versionType": "git" }, { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "25c8c7fb3b0b9668c7d05e209f58c158d2b020c7", "status": "affected", "versionType": "git" }, { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "42827d03f8009a6a218bacab153e21f39d6a121c", "status": "affected", "versionType": "git" }, { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "88697cf980222d5906a37bf47662dac0732e2a0f", "status": "affected", "versionType": "git" }, { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "b5316e2b8614a87d8736941972441cb47bfd4491", "status": "affected", "versionType": "git" }, { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "ec82ea4eb220164d854f8734ca5a35e23e577b94", "status": "affected", "versionType": "git" }, { "version": "6be3b0db6db82cf056a72cc18042048edd27f8ee", "lessThan": "7f2d76c9c03257c0782afef9d95321fa04096f60", "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_policy.c" ], "versions": [ { "version": "5.0", "status": "affected" }, { "version": "0", "lessThan": "5.0", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.259", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.176", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.143", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.94", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.36", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.13", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "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": "5.0", "versionEndExcluding": "5.10.259" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0", "versionEndExcluding": "5.15.210" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0", "versionEndExcluding": "6.1.176" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0", "versionEndExcluding": "6.6.143" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0", "versionEndExcluding": "6.12.94" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0", "versionEndExcluding": "6.18.36" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0", "versionEndExcluding": "7.0.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/8fc536e9f6856230f19c7d13e71af064b6a77b22" }, { "url": "https://git.kernel.org/stable/c/c4c1ea36d83bf3c4569468ca5b8b614fda1bf821" }, { "url": "https://git.kernel.org/stable/c/25c8c7fb3b0b9668c7d05e209f58c158d2b020c7" }, { "url": "https://git.kernel.org/stable/c/42827d03f8009a6a218bacab153e21f39d6a121c" }, { "url": "https://git.kernel.org/stable/c/88697cf980222d5906a37bf47662dac0732e2a0f" }, { "url": "https://git.kernel.org/stable/c/b5316e2b8614a87d8736941972441cb47bfd4491" }, { "url": "https://git.kernel.org/stable/c/ec82ea4eb220164d854f8734ca5a35e23e577b94" }, { "url": "https://git.kernel.org/stable/c/7f2d76c9c03257c0782afef9d95321fa04096f60" } ], "title": "xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx()", "x_generator": { "engine": "bippy-1.2.0" } } } }