CVE-2025-40215 (GCVE-0-2025-40215)
Vulnerability from cvelistv5 – Published: 2025-12-04 12:38 – Updated: 2026-08-05 12:08
VLAI
EPSS
VEX
Title
xfrm: delete x->tunnel as we delete x
Summary
In the Linux kernel, the following vulnerability has been resolved:
xfrm: delete x->tunnel as we delete x
The ipcomp fallback tunnels currently get deleted (from the various
lists and hashtables) as the last user state that needed that fallback
is destroyed (not deleted). If a reference to that user state still
exists, the fallback state will remain on the hashtables/lists,
triggering the WARN in xfrm_state_fini. Because of those remaining
references, the fix in commit f75a2804da39 ("xfrm: destroy xfrm_state
synchronously on net exit path") is not complete.
We recently fixed one such situation in TCP due to defered freeing of
skbs (commit 9b6412e6979f ("tcp: drop secpath at the same time as we
currently drop dst")). This can also happen due to IP reassembly: skbs
with a secpath remain on the reassembly queue until netns
destruction. If we can't guarantee that the queues are flushed by the
time xfrm_state_fini runs, there may still be references to a (user)
xfrm_state, preventing the timely deletion of the corresponding
fallback state.
Instead of chasing each instance of skbs holding a secpath one by one,
this patch fixes the issue directly within xfrm, by deleting the
fallback state as soon as the last user state depending on it has been
deleted. Destruction will still happen when the final reference is
dropped.
A separate lockdep class for the fallback state is required since
we're going to lock x->tunnel while x is locked.
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-16 19:56 UTC
Assigner
References
6 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
9d4139c76905833afcb77fe8ccc17f302a0eb9ab , < 1b28a7fae0128fa140a7dccd995182ff6cd1c67b
(git)
Affected: 9d4139c76905833afcb77fe8ccc17f302a0eb9ab , < 4b2c17d0f9be8b58bb30468bc81a4b61c985b04e (git) Affected: 9d4139c76905833afcb77fe8ccc17f302a0eb9ab , < 0da961fa46da1b37ef868d9b603bd202136f8f8e (git) Affected: 9d4139c76905833afcb77fe8ccc17f302a0eb9ab , < d0e0d1097118461463b76562c7ebaabaa5b90b13 (git) Affected: 9d4139c76905833afcb77fe8ccc17f302a0eb9ab , < dc3636912d41770466543623cb76e7b88fdb42c7 (git) Affected: 9d4139c76905833afcb77fe8ccc17f302a0eb9ab , < b441cf3f8c4b8576639d20c8eb4aa32917602ecd (git) |
guessed | |
| Linux | Linux |
Affected:
2.6.29
Unaffected: 0 , < 2.6.29 (semver) Unaffected: 5.10.248 , ≤ 5.10.* (semver) Unaffected: 5.15.198 , ≤ 5.15.* (semver) Unaffected: 6.1.160 , ≤ 6.1.* (semver) Unaffected: 6.6.120 , ≤ 6.6.* (semver) Unaffected: 6.12.62 , ≤ 6.12.* (semver) Unaffected: 6.16 , ≤ * (original_commit_for_fix) |
guessed |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2025-40215",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-06-16T19:56:10.578142Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-06-16T19:56:19.286Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"include/net/xfrm.h",
"net/ipv4/ipcomp.c",
"net/ipv6/ipcomp6.c",
"net/ipv6/xfrm6_tunnel.c",
"net/xfrm/xfrm_ipcomp.c",
"net/xfrm/xfrm_state.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "1b28a7fae0128fa140a7dccd995182ff6cd1c67b",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "4b2c17d0f9be8b58bb30468bc81a4b61c985b04e",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "0da961fa46da1b37ef868d9b603bd202136f8f8e",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "d0e0d1097118461463b76562c7ebaabaa5b90b13",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "dc3636912d41770466543623cb76e7b88fdb42c7",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "b441cf3f8c4b8576639d20c8eb4aa32917602ecd",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"include/net/xfrm.h",
"net/ipv4/ipcomp.c",
"net/ipv6/ipcomp6.c",
"net/ipv6/xfrm6_tunnel.c",
"net/xfrm/xfrm_ipcomp.c",
"net/xfrm/xfrm_state.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.29"
},
{
"lessThan": "2.6.29",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.248",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.198",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.160",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.120",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.62",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.16",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.10.248",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.198",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.160",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.120",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.62",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.16",
"versionStartIncluding": "2.6.29",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: delete x-\u003etunnel as we delete x\n\nThe ipcomp fallback tunnels currently get deleted (from the various\nlists and hashtables) as the last user state that needed that fallback\nis destroyed (not deleted). If a reference to that user state still\nexists, the fallback state will remain on the hashtables/lists,\ntriggering the WARN in xfrm_state_fini. Because of those remaining\nreferences, the fix in commit f75a2804da39 (\"xfrm: destroy xfrm_state\nsynchronously on net exit path\") is not complete.\n\nWe recently fixed one such situation in TCP due to defered freeing of\nskbs (commit 9b6412e6979f (\"tcp: drop secpath at the same time as we\ncurrently drop dst\")). This can also happen due to IP reassembly: skbs\nwith a secpath remain on the reassembly queue until netns\ndestruction. If we can\u0027t guarantee that the queues are flushed by the\ntime xfrm_state_fini runs, there may still be references to a (user)\nxfrm_state, preventing the timely deletion of the corresponding\nfallback state.\n\nInstead of chasing each instance of skbs holding a secpath one by one,\nthis patch fixes the issue directly within xfrm, by deleting the\nfallback state as soon as the last user state depending on it has been\ndeleted. Destruction will still happen when the final reference is\ndropped.\n\nA separate lockdep class for the fallback state is required since\nwe\u0027re going to lock x-\u003etunnel while x is locked."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - Triggering requires locally configuring an IPComp tunnel-mode SA via XFRM netlink and then tearing down the network namespace; a purely remote peer can pin the secpath reference but cannot create the SA or cause the netns teardown that frees the hash tables.\nAC:L - The attacker controls every element \u2014 SA creation, injecting the IPComp/fragmented packet that leaves an skb secpath reference outstanding, and the timing of namespace destruction \u2014 and the 30-second reassembly-queue window gives a large, reliable interval to groom the reclaimed kmalloc-64 bucket array and struct net.\nPR:L - XFRM state configuration is gated on netlink_net_capable(CAP_NET_ADMIN), which an unprivileged user obtains over their own namespace with `unshare -Urn`, and the ipcomp module autoloads via request_module() with no capability check.\nUI:N - The entire sequence \u2014 SA setup, packet injection, namespace exit \u2014 is performed by the attacker\u0027s own process with no action by any other user.\nS:U - The corrupted objects (xfrm hash tables, struct net, pernet data) and the vulnerable code are both kernel-resident, so impact stays within the kernel\u0027s security authority.\nC:H - The stale state is unlinked from already-freed memory, so its list/hlist traversal reads reclaimed slab contents and leaks kernel pointers into attacker-controllable objects, which is leverageable for arbitrary kernel memory disclosure.\nI:H - __xfrm_state_delete() performs list_del()/hlist_del_rcu() and net-\u003exfrm.state_num-- on a freed struct net and a freed 64-byte bucket array, writing heap pointers at controlled offsets into reclaimed slab objects \u2014 a use-after-free write primitive usable for control-flow hijack.\nA:H - The bug immediately trips WARN_ON() in xfrm_state_fini() and xfrm6_tunnel_net_exit() (panic with panic_on_warn), and the subsequent use-after-free \u2014 including spin_lock() on freed memory \u2014 reliably produces oopses, lock corruption, or a full kernel panic."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-05T12:08:40.873Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/1b28a7fae0128fa140a7dccd995182ff6cd1c67b"
},
{
"url": "https://git.kernel.org/stable/c/4b2c17d0f9be8b58bb30468bc81a4b61c985b04e"
},
{
"url": "https://git.kernel.org/stable/c/0da961fa46da1b37ef868d9b603bd202136f8f8e"
},
{
"url": "https://git.kernel.org/stable/c/d0e0d1097118461463b76562c7ebaabaa5b90b13"
},
{
"url": "https://git.kernel.org/stable/c/dc3636912d41770466543623cb76e7b88fdb42c7"
},
{
"url": "https://git.kernel.org/stable/c/b441cf3f8c4b8576639d20c8eb4aa32917602ecd"
}
],
"title": "xfrm: delete x-\u003etunnel as we delete x",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2025-40215",
"datePublished": "2025-12-04T12:38:32.517Z",
"dateReserved": "2025-04-16T07:20:57.179Z",
"dateUpdated": "2026-08-05T12:08:40.873Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2025-40215",
"date": "2026-09-24",
"epss": "0.00144",
"percentile": "0.03023"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"include/net/xfrm.h",
"net/ipv4/ipcomp.c",
"net/ipv6/ipcomp6.c",
"net/ipv6/xfrm6_tunnel.c",
"net/xfrm/xfrm_ipcomp.c",
"net/xfrm/xfrm_state.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "1b28a7fae0128fa140a7dccd995182ff6cd1c67b",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "4b2c17d0f9be8b58bb30468bc81a4b61c985b04e",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "0da961fa46da1b37ef868d9b603bd202136f8f8e",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "d0e0d1097118461463b76562c7ebaabaa5b90b13",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "dc3636912d41770466543623cb76e7b88fdb42c7",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "b441cf3f8c4b8576639d20c8eb4aa32917602ecd",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"include/net/xfrm.h",
"net/ipv4/ipcomp.c",
"net/ipv6/ipcomp6.c",
"net/ipv6/xfrm6_tunnel.c",
"net/xfrm/xfrm_ipcomp.c",
"net/xfrm/xfrm_state.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.29"
},
{
"lessThan": "2.6.29",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.248",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.198",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.160",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.120",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.62",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.16",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: delete x-\u003etunnel as we delete x\n\nThe ipcomp fallback tunnels currently get deleted (from the various\nlists and hashtables) as the last user state that needed that fallback\nis destroyed (not deleted). If a reference to that user state still\nexists, the fallback state will remain on the hashtables/lists,\ntriggering the WARN in xfrm_state_fini. Because of those remaining\nreferences, the fix in commit f75a2804da39 (\"xfrm: destroy xfrm_state\nsynchronously on net exit path\") is not complete.\n\nWe recently fixed one such situation in TCP due to defered freeing of\nskbs (commit 9b6412e6979f (\"tcp: drop secpath at the same time as we\ncurrently drop dst\")). This can also happen due to IP reassembly: skbs\nwith a secpath remain on the reassembly queue until netns\ndestruction. If we can\u0027t guarantee that the queues are flushed by the\ntime xfrm_state_fini runs, there may still be references to a (user)\nxfrm_state, preventing the timely deletion of the corresponding\nfallback state.\n\nInstead of chasing each instance of skbs holding a secpath one by one,\nthis patch fixes the issue directly within xfrm, by deleting the\nfallback state as soon as the last user state depending on it has been\ndeleted. Destruction will still happen when the final reference is\ndropped.\n\nA separate lockdep class for the fallback state is required since\nwe\u0027re going to lock x-\u003etunnel while x is locked."
}
],
"id": "CVE-2025-40215",
"lastModified": "2026-07-30T06:24:18.487",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2025-40215",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-06-16T19:56:10.578142Z",
"version": "2.0.3"
}
}
]
},
"published": "2025-12-04T13:15:48.473",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/0da961fa46da1b37ef868d9b603bd202136f8f8e"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/1b28a7fae0128fa140a7dccd995182ff6cd1c67b"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/4b2c17d0f9be8b58bb30468bc81a4b61c985b04e"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/b441cf3f8c4b8576639d20c8eb4aa32917602ecd"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/d0e0d1097118461463b76562c7ebaabaa5b90b13"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/dc3636912d41770466543623cb76e7b88fdb42c7"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Deferred"
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-07-30T08:48:19+00:00",
"cve": "CVE-2025-40215",
"id": "CVE-2025-40215",
"initial_release_date": "2025-12-04T00:00:00+00:00",
"product_status:known_affected": "274",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: xfrm: delete x-\u003etunnel as we delete x",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40215.json",
"version": "3"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2025-40215",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-06-16T19:56:10.578142Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-06-16T19:56:15.418Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"include/net/xfrm.h",
"net/ipv4/ipcomp.c",
"net/ipv6/ipcomp6.c",
"net/ipv6/xfrm6_tunnel.c",
"net/xfrm/xfrm_ipcomp.c",
"net/xfrm/xfrm_state.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "1b28a7fae0128fa140a7dccd995182ff6cd1c67b",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "4b2c17d0f9be8b58bb30468bc81a4b61c985b04e",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "0da961fa46da1b37ef868d9b603bd202136f8f8e",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "d0e0d1097118461463b76562c7ebaabaa5b90b13",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "dc3636912d41770466543623cb76e7b88fdb42c7",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
},
{
"lessThan": "b441cf3f8c4b8576639d20c8eb4aa32917602ecd",
"status": "affected",
"version": "9d4139c76905833afcb77fe8ccc17f302a0eb9ab",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"include/net/xfrm.h",
"net/ipv4/ipcomp.c",
"net/ipv6/ipcomp6.c",
"net/ipv6/xfrm6_tunnel.c",
"net/xfrm/xfrm_ipcomp.c",
"net/xfrm/xfrm_state.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.29"
},
{
"lessThan": "2.6.29",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.248",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.198",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.160",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.120",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.62",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.16",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.10.248",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.198",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.160",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.120",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.62",
"versionStartIncluding": "2.6.29",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.16",
"versionStartIncluding": "2.6.29",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: delete x-\u003etunnel as we delete x\n\nThe ipcomp fallback tunnels currently get deleted (from the various\nlists and hashtables) as the last user state that needed that fallback\nis destroyed (not deleted). If a reference to that user state still\nexists, the fallback state will remain on the hashtables/lists,\ntriggering the WARN in xfrm_state_fini. Because of those remaining\nreferences, the fix in commit f75a2804da39 (\"xfrm: destroy xfrm_state\nsynchronously on net exit path\") is not complete.\n\nWe recently fixed one such situation in TCP due to defered freeing of\nskbs (commit 9b6412e6979f (\"tcp: drop secpath at the same time as we\ncurrently drop dst\")). This can also happen due to IP reassembly: skbs\nwith a secpath remain on the reassembly queue until netns\ndestruction. If we can\u0027t guarantee that the queues are flushed by the\ntime xfrm_state_fini runs, there may still be references to a (user)\nxfrm_state, preventing the timely deletion of the corresponding\nfallback state.\n\nInstead of chasing each instance of skbs holding a secpath one by one,\nthis patch fixes the issue directly within xfrm, by deleting the\nfallback state as soon as the last user state depending on it has been\ndeleted. Destruction will still happen when the final reference is\ndropped.\n\nA separate lockdep class for the fallback state is required since\nwe\u0027re going to lock x-\u003etunnel while x is locked."
}
],
"providerMetadata": {
"dateUpdated": "2026-05-11T21:44:59.604Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/1b28a7fae0128fa140a7dccd995182ff6cd1c67b"
},
{
"url": "https://git.kernel.org/stable/c/4b2c17d0f9be8b58bb30468bc81a4b61c985b04e"
},
{
"url": "https://git.kernel.org/stable/c/0da961fa46da1b37ef868d9b603bd202136f8f8e"
},
{
"url": "https://git.kernel.org/stable/c/d0e0d1097118461463b76562c7ebaabaa5b90b13"
},
{
"url": "https://git.kernel.org/stable/c/dc3636912d41770466543623cb76e7b88fdb42c7"
},
{
"url": "https://git.kernel.org/stable/c/b441cf3f8c4b8576639d20c8eb4aa32917602ecd"
}
],
"title": "xfrm: delete x-\u003etunnel as we delete x",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2025-40215",
"datePublished": "2025-12-04T12:38:32.517Z",
"dateReserved": "2025-04-16T07:20:57.179Z",
"dateUpdated": "2026-06-16T19:56:19.286Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…