{"id":"CVE-2026-72463","state":"PUBLISHED","title":"xfrm: Fix dev use-after-free in xfrm async resumption","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Fix dev use-after-free in xfrm async resumption\n\nxfrm async resumption hold skb->dev refcnt until after transport_finish.\nHowever, xfrm_rcv_cb may modify skb->dev to tunnel dev without taking\ndevice reference, such as vti_rcv_cb. The subsequent async resumption\nwill decrement the tunnel device's reference count, which lead to uaf\nof tunnel dev and refcnt leak of orig dev as below:\n\nunregister_netdevice: waiting for vti1 to become free. Usage count = -2\n\nStash the original skb->dev to fix refcnt imbalance. The new skb->dev set\nby xfrm_rcv_cb can race with device teardown. Extend rcu protection over\nxfrm_rcv_cb and transport_finish to prevent races.","publishedAt":"2026-08-15T05:57:07.413Z","updatedAt":"2026-10-30T12:29:27.386Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4236c30b437b80f673b9e08c8fae38b8d471ac9e","status":"affected","lessThan":"fed4d3195a31125566876952ce66113ec1eb9008","versionType":"git"},{"version":"0f451b43c88bf2b9c038b414be580efee42e031b","status":"affected","lessThan":"1acd93259b6be269e26be5d71c224bccd1f8352f","versionType":"git"},{"version":"1c428b03840094410c5fb6a5db30640486bbbfcb","status":"affected","lessThan":"63a30015199912bd5055bead8001b1ae68a67cdb","versionType":"git"},{"version":"1c428b03840094410c5fb6a5db30640486bbbfcb","status":"affected","lessThan":"8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff","versionType":"git"},{"version":"4d06caedea587c59cc2cc893ceecc57c75c64312","status":"affected","versionType":"git"},{"version":"94439cbe478b53f92223da9aae95fffb28623c3f","status":"affected","versionType":"git"},{"version":"5002beda5cac69d522dc54da0d5d463ed9c963d2","status":"affected","versionType":"git"},{"version":"6.12.94","status":"affected","lessThan":"6.12.112","versionType":"semver"},{"version":"6.18.23","status":"affected","lessThan":"6.18.54","versionType":"semver"},{"version":"6.1.191","status":"affected","lessThan":"6.2","versionType":"semver"},{"version":"6.6.160","status":"affected","lessThan":"6.7","versionType":"semver"},{"version":"6.19.13","status":"affected","lessThan":"6.20","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/xfrm4_input.c","net/ipv6/xfrm6_input.c","net/xfrm/xfrm_input.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.0","versionType":"semver"},{"version":"6.12.112","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.54","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/xfrm4_input.c","net/ipv6/xfrm6_input.c","net/xfrm/xfrm_input.c"]}],"references":["https://git.kernel.org/stable/c/fed4d3195a31125566876952ce66113ec1eb9008","https://git.kernel.org/stable/c/1acd93259b6be269e26be5d71c224bccd1f8352f","https://git.kernel.org/stable/c/63a30015199912bd5055bead8001b1ae68a67cdb","https://git.kernel.org/stable/c/8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff"],"weaknesses":[],"ingestedAt":"2026-10-30T12:48:04.825Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72463.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72463","state":"PUBLISHED","datePublished":"2026-08-15T05:57:07.413Z","dateUpdated":"2026-10-30T12:29:27.386Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-09T03:40:39.933Z"},"containers":{"cna":{"title":"xfrm: Fix dev use-after-free in xfrm async resumption","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Fix dev use-after-free in xfrm async resumption\n\nxfrm async resumption hold skb->dev refcnt until after transport_finish.\nHowever, xfrm_rcv_cb may modify skb->dev to tunnel dev without taking\ndevice reference, such as vti_rcv_cb. The subsequent async resumption\nwill decrement the tunnel device's reference count, which lead to uaf\nof tunnel dev and refcnt leak of orig dev as below:\n\nunregister_netdevice: waiting for vti1 to become free. Usage count = -2\n\nStash the original skb->dev to fix refcnt imbalance. The new skb->dev set\nby xfrm_rcv_cb can race with device teardown. Extend rcu protection over\nxfrm_rcv_cb and transport_finish to prevent races."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4236c30b437b80f673b9e08c8fae38b8d471ac9e","status":"affected","lessThan":"fed4d3195a31125566876952ce66113ec1eb9008","versionType":"git"},{"version":"0f451b43c88bf2b9c038b414be580efee42e031b","status":"affected","lessThan":"1acd93259b6be269e26be5d71c224bccd1f8352f","versionType":"git"},{"version":"1c428b03840094410c5fb6a5db30640486bbbfcb","status":"affected","lessThan":"63a30015199912bd5055bead8001b1ae68a67cdb","versionType":"git"},{"version":"1c428b03840094410c5fb6a5db30640486bbbfcb","status":"affected","lessThan":"8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff","versionType":"git"},{"version":"4d06caedea587c59cc2cc893ceecc57c75c64312","status":"affected","versionType":"git"},{"version":"94439cbe478b53f92223da9aae95fffb28623c3f","status":"affected","versionType":"git"},{"version":"5002beda5cac69d522dc54da0d5d463ed9c963d2","status":"affected","versionType":"git"},{"version":"6.12.94","status":"affected","lessThan":"6.12.112","versionType":"semver"},{"version":"6.18.23","status":"affected","lessThan":"6.18.54","versionType":"semver"},{"version":"6.1.191","status":"affected","lessThan":"6.2","versionType":"semver"},{"version":"6.6.160","status":"affected","lessThan":"6.7","versionType":"semver"},{"version":"6.19.13","status":"affected","lessThan":"6.20","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/xfrm4_input.c","net/ipv6/xfrm6_input.c","net/xfrm/xfrm_input.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.0","versionType":"semver"},{"version":"6.12.112","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.54","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/xfrm4_input.c","net/ipv6/xfrm6_input.c","net/xfrm/xfrm_input.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/fed4d3195a31125566876952ce66113ec1eb9008"},{"url":"https://git.kernel.org/stable/c/1acd93259b6be269e26be5d71c224bccd1f8352f"},{"url":"https://git.kernel.org/stable/c/63a30015199912bd5055bead8001b1ae68a67cdb"},{"url":"https://git.kernel.org/stable/c/8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff"}],"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 - Reachable from the network receive path: remote ESP/AH (or UDP-encapsulated IPsec) packets hit ip_rcv → xfrm4/xfrm6 protocol handlers → vti/xfrmi input → xfrm_input() → async crypto resume, on Internet-facing IPsec/VTI/xfrmi VPN gateways and cloud endpoints.\nAC:L - Once async decryption resumes (encap_type=-1), vti_rcv_cb/xfrmi_rcv_cb retarget skb->dev and the stale dev_put is deterministic; the attacker controls packet rate/volume to drive -EINPROGRESS and can race netdev teardown, so no uncontrollable victim-only conditions apply.\nPR:N - No local account, shell, or capability on the victim is required—only network-delivered IPsec traffic accepted by a pre-configured VTI/xfrmi gateway (e.g., VPN peer, site-to-site endpoint); administrative IPsec setup is deployment state, not attacker privilege on the host.\nUI:N - Exploitation is fully automated by sending IPsec packets; no victim interaction such as mounting filesystems, opening files, or clicking links is needed.\nS:U - Impact is kernel net_device refcount corruption/UAF within the host kernel security authority; it does not cross VM, IOMMU, or sandbox boundaries (standard kernel privilege escalation, not escape).\nC:H - Use-after-free of a net_device after refcount underflow (e.g., usage count=-2) exposes freed netdev/slab memory; per kernel UAF guidance this provides a high-impact arbitrary-read primitive via heap grooming.\nI:H - Corrupting freed net_device structures and reference counts is classic heap UAF that can be shaped into arbitrary kernel writes and control-flow hijack for code execution, per kernel memory-corruption guidance.\nA:H - Refcount imbalance causes unregister_netdevice to hang (usage count=-2), kernel oops/panic during tunnel teardown, and reliable denial of service on IPsec gateways even before full exploitation."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:29:27.386Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.94","versionEndExcluding":"6.12.112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18.23","versionEndExcluding":"6.18.54"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19.13"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}