{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72463", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.933Z", "datePublished": "2026-08-15T05:57:07.413Z", "dateUpdated": "2026-08-17T05:44:29.613Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:44:29.613Z" }, "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." } ], "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." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "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" ], "versions": [ { "version": "1c428b03840094410c5fb6a5db30640486bbbfcb", "lessThan": "63a30015199912bd5055bead8001b1ae68a67cdb", "status": "affected", "versionType": "git" }, { "version": "1c428b03840094410c5fb6a5db30640486bbbfcb", "lessThan": "8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff", "status": "affected", "versionType": "git" }, { "version": "4236c30b437b80f673b9e08c8fae38b8d471ac9e", "status": "affected", "versionType": "git" }, { "version": "0f451b43c88bf2b9c038b414be580efee42e031b", "status": "affected", "versionType": "git" }, { "version": "5002beda5cac69d522dc54da0d5d463ed9c963d2", "status": "affected", "versionType": "git" }, { "version": "6.12.94", "lessThan": "6.13", "status": "affected", "versionType": "semver" }, { "version": "6.18.23", "lessThan": "6.19", "status": "affected", "versionType": "semver" }, { "version": "6.19.13", "lessThan": "6.20", "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/ipv4/xfrm4_input.c", "net/ipv6/xfrm6_input.c", "net/xfrm/xfrm_input.c" ], "versions": [ { "version": "7.0", "status": "affected" }, { "version": "0", "lessThan": "7.0", "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": "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": "6.12.94" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.23" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19.13" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/63a30015199912bd5055bead8001b1ae68a67cdb" }, { "url": "https://git.kernel.org/stable/c/8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff" } ], "title": "xfrm: Fix dev use-after-free in xfrm async resumption", "x_generator": { "engine": "bippy-1.2.0" } } } }