CVE-2026-43499 (GCVE-0-2026-43499)
Vulnerability from cvelistv5 – Published: 2026-05-21 12:17 – Updated: 2026-05-21 12:17
VLAI?
Title
rtmutex: Use waiter::task instead of current in remove_waiter()
Summary
In the Linux kernel, the following vulnerability has been resolved:
rtmutex: Use waiter::task instead of current in remove_waiter()
remove_waiter() is used by the slowlock paths, but it is also used for
proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from
futex_requeue().
In the latter case waiter::task is not current, but remove_waiter()
operates on current for the dequeue operation. That results in several
problems:
1) the rbtree dequeue happens without waiter::task::pi_lock being held
2) the waiter task's pi_blocked_on state is not cleared, which leaves a
dangling pointer primed for UAF around.
3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter
task
Use waiter::task instead of current in all related operations in
remove_waiter() to cure those problems.
[ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the
changelog ]
Severity ?
No CVSS data available.
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| Linux | Linux |
Affected:
8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 8a1fc8d698ac5e5916e3082a0f74450d71f9611f
(git)
Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 6d52dfcb2a5db86e346cf51f8fcf2071b8085166 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 3fb7394a837740770f0d6b4b30567e60786a63f2 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 88614876370aac8ad1050ad785a4c095ba17ac11 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 3bfdc63936dd4773109b7b8c280c0f3b5ae7d349 (git) |
|
| Linux | Linux |
Affected:
2.6.39
Unaffected: 0 , < 2.6.39 (semver) Unaffected: 6.6.140 , ≤ 6.6.* (semver) Unaffected: 6.12.86 , ≤ 6.12.* (semver) Unaffected: 6.18.27 , ≤ 6.18.* (semver) Unaffected: 7.0.4 , ≤ 7.0.* (semver) Unaffected: 7.1-rc1 , ≤ * (original_commit_for_fix) |
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"kernel/locking/rtmutex.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "8a1fc8d698ac5e5916e3082a0f74450d71f9611f",
"status": "affected",
"version": "8161239a8bcce9ad6b537c04a1fa3b5c68bae693",
"versionType": "git"
},
{
"lessThan": "6d52dfcb2a5db86e346cf51f8fcf2071b8085166",
"status": "affected",
"version": "8161239a8bcce9ad6b537c04a1fa3b5c68bae693",
"versionType": "git"
},
{
"lessThan": "3fb7394a837740770f0d6b4b30567e60786a63f2",
"status": "affected",
"version": "8161239a8bcce9ad6b537c04a1fa3b5c68bae693",
"versionType": "git"
},
{
"lessThan": "88614876370aac8ad1050ad785a4c095ba17ac11",
"status": "affected",
"version": "8161239a8bcce9ad6b537c04a1fa3b5c68bae693",
"versionType": "git"
},
{
"lessThan": "3bfdc63936dd4773109b7b8c280c0f3b5ae7d349",
"status": "affected",
"version": "8161239a8bcce9ad6b537c04a1fa3b5c68bae693",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"kernel/locking/rtmutex.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.39"
},
{
"lessThan": "2.6.39",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.140",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.86",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.27",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.4",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.1-rc1",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.140",
"versionStartIncluding": "2.6.39",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.86",
"versionStartIncluding": "2.6.39",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.27",
"versionStartIncluding": "2.6.39",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.0.4",
"versionStartIncluding": "2.6.39",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1-rc1",
"versionStartIncluding": "2.6.39",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrtmutex: Use waiter::task instead of current in remove_waiter()\n\nremove_waiter() is used by the slowlock paths, but it is also used for\nproxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from\nfutex_requeue().\n\nIn the latter case waiter::task is not current, but remove_waiter()\noperates on current for the dequeue operation. That results in several\nproblems:\n\n 1) the rbtree dequeue happens without waiter::task::pi_lock being held\n\n 2) the waiter task\u0027s pi_blocked_on state is not cleared, which leaves a\n dangling pointer primed for UAF around.\n\n 3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter\n task\n\nUse waiter::task instead of current in all related operations in\nremove_waiter() to cure those problems.\n\n[ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the\n \tchangelog ]"
}
],
"providerMetadata": {
"dateUpdated": "2026-05-21T12:17:49.281Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/8a1fc8d698ac5e5916e3082a0f74450d71f9611f"
},
{
"url": "https://git.kernel.org/stable/c/6d52dfcb2a5db86e346cf51f8fcf2071b8085166"
},
{
"url": "https://git.kernel.org/stable/c/3fb7394a837740770f0d6b4b30567e60786a63f2"
},
{
"url": "https://git.kernel.org/stable/c/88614876370aac8ad1050ad785a4c095ba17ac11"
},
{
"url": "https://git.kernel.org/stable/c/3bfdc63936dd4773109b7b8c280c0f3b5ae7d349"
}
],
"title": "rtmutex: Use waiter::task instead of current in remove_waiter()",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-43499",
"datePublished": "2026-05-21T12:17:49.281Z",
"dateReserved": "2026-05-01T14:12:56.014Z",
"dateUpdated": "2026-05-21T12:17:49.281Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"nvd": "{\"cve\":{\"id\":\"CVE-2026-43499\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-05-21T13:16:19.300\",\"lastModified\":\"2026-05-21T13:16:19.300\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nrtmutex: Use waiter::task instead of current in remove_waiter()\\n\\nremove_waiter() is used by the slowlock paths, but it is also used for\\nproxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from\\nfutex_requeue().\\n\\nIn the latter case waiter::task is not current, but remove_waiter()\\noperates on current for the dequeue operation. That results in several\\nproblems:\\n\\n 1) the rbtree dequeue happens without waiter::task::pi_lock being held\\n\\n 2) the waiter task\u0027s pi_blocked_on state is not cleared, which leaves a\\n dangling pointer primed for UAF around.\\n\\n 3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter\\n task\\n\\nUse waiter::task instead of current in all related operations in\\nremove_waiter() to cure those problems.\\n\\n[ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the\\n \\tchangelog ]\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/3bfdc63936dd4773109b7b8c280c0f3b5ae7d349\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3fb7394a837740770f0d6b4b30567e60786a63f2\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/6d52dfcb2a5db86e346cf51f8fcf2071b8085166\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/88614876370aac8ad1050ad785a4c095ba17ac11\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8a1fc8d698ac5e5916e3082a0f74450d71f9611f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
}
}
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…