CVE-2022-49256
Status: AnalyzedMedium (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
watch_queue: Actually free the watch
free_watch() does everything barring actually freeing the watch object. Fix this by adding the missing kfree.
kmemleak produces a report something like the following. Note that as an address can be seen in the first word, the watch would appear to have gone through call_rcu().
Technical details traces, logs and code from the original report
BUG: memory leak
unreferenced object 0xffff88810ce4a200 (size 96):
comm "syz-executor352", pid 3605, jiffies 4294947473 (age 13.720s)
hex dump (first 32 bytes):
e0 82 48 0d 81 88 ff ff 00 00 00 00 00 00 00 00 ..H.............
80 a2 e4 0c 81 88 ff ff 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff8214e6cc>] kmalloc include/linux/slab.h:581 [inline]
[<ffffffff8214e6cc>] kzalloc include/linux/slab.h:714 [inline]
[<ffffffff8214e6cc>] keyctl_watch_key+0xec/0x2e0 security/keys/keyctl.c:1800
[<ffffffff8214ec84>] __do_sys_keyctl+0x3c4/0x490 security/keys/keyctl.c:2016
[<ffffffff84493a25>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff84493a25>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff84600068>] entry_SYSCALL_64_after_hwframe+0x44/0xaeCVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Base score: 5.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.26%
- Percentile among all scored CVEs: 16
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
CWEs
- CWE-401
References
- https://git.kernel.org/stable/c/31824613a42aacdcbeb325bf07a1c8247a11ebe2
- https://git.kernel.org/stable/c/3d8dcf278b1ee1eff1e90be848fa2237db4c07a7
- https://git.kernel.org/stable/c/7e8c9b0df07a77f0d072603b8ced2677e30e1893
- https://git.kernel.org/stable/c/9d92be1a09fbb3dd65600dbfe7eedb40e7228e4b
- https://git.kernel.org/stable/c/f69aecb49968e14196366bbe896eab0a904229f5
Raw JSON (NVD)
Show
{
"id": "CVE-2022-49256",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 5.5,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 1.8
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "c73be61cede5882f9605a852414db559c0ebedfd",
"lessThan": "9d92be1a09fbb3dd65600dbfe7eedb40e7228e4b",
"versionType": "git"
},
{
"status": "affected",
"version": "c73be61cede5882f9605a852414db559c0ebedfd",
"lessThan": "f69aecb49968e14196366bbe896eab0a904229f5",
"versionType": "git"
},
{
"status": "affected",
"version": "c73be61cede5882f9605a852414db559c0ebedfd",
"lessThan": "7e8c9b0df07a77f0d072603b8ced2677e30e1893",
"versionType": "git"
},
{
"status": "affected",
"version": "c73be61cede5882f9605a852414db559c0ebedfd",
"lessThan": "31824613a42aacdcbeb325bf07a1c8247a11ebe2",
"versionType": "git"
},
{
"status": "affected",
"version": "c73be61cede5882f9605a852414db559c0ebedfd",
"lessThan": "3d8dcf278b1ee1eff1e90be848fa2237db4c07a7",
"versionType": "git"
}
],
"programFiles": [
"kernel/watch_queue.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.8"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.8",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.110",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.33",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "5.16.19",
"versionType": "semver",
"lessThanOrEqual": "5.16.*"
},
{
"status": "unaffected",
"version": "5.17.2",
"versionType": "semver",
"lessThanOrEqual": "5.17.*"
},
{
"status": "unaffected",
"version": "5.18",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/watch_queue.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2025-02-26T07:01:02.497",
"references": [
{
"url": "https://git.kernel.org/stable/c/31824613a42aacdcbeb325bf07a1c8247a11ebe2",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3d8dcf278b1ee1eff1e90be848fa2237db4c07a7",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7e8c9b0df07a77f0d072603b8ced2677e30e1893",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/9d92be1a09fbb3dd65600dbfe7eedb40e7228e4b",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f69aecb49968e14196366bbe896eab0a904229f5",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-401"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nwatch_queue: Actually free the watch\n\nfree_watch() does everything barring actually freeing the watch object. Fix\nthis by adding the missing kfree.\n\nkmemleak produces a report something like the following. Note that as an\naddress can be seen in the first word, the watch would appear to have gone\nthrough call_rcu().\n\nBUG: memory leak\nunreferenced object 0xffff88810ce4a200 (size 96):\n comm \"syz-executor352\", pid 3605, jiffies 4294947473 (age 13.720s)\n hex dump (first 32 bytes):\n e0 82 48 0d 81 88 ff ff 00 00 00 00 00 00 00 00 ..H.............\n 80 a2 e4 0c 81 88 ff ff 00 00 00 00 00 00 00 00 ................\n backtrace:\n [<ffffffff8214e6cc>] kmalloc include/linux/slab.h:581 [inline]\n [<ffffffff8214e6cc>] kzalloc include/linux/slab.h:714 [inline]\n [<ffffffff8214e6cc>] keyctl_watch_key+0xec/0x2e0 security/keys/keyctl.c:1800\n [<ffffffff8214ec84>] __do_sys_keyctl+0x3c4/0x490 security/keys/keyctl.c:2016\n [<ffffffff84493a25>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n [<ffffffff84493a25>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\n [<ffffffff84600068>] entry_SYSCALL_64_after_hwframe+0x44/0xae"
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: watch_queue: En realidad, libera el reloj. free_watch() hace todo lo posible, excepto liberar realmente el objeto de vigilancia. Solucione esto agregando el kfree faltante. kmemleak produce un informe similar al siguiente. Tenga en cuenta que, como se puede ver una dirección en la primera palabra, el reloj parecería haber pasado por call_rcu(). ERROR: pérdida de memoria objeto no referenciado 0xffff88810ce4a200 (tamaño 96): comm \"syz-executor352\", pid 3605, jiffies 4294947473 (edad 13.720s) volcado hexadecimal (primeros 32 bytes): e0 82 48 0d 81 88 ff ff 00 00 00 00 00 00 00 00 ..H............. 80 a2 e4 0c 81 88 ff ff 00 00 00 00 00 00 00 00 ................ backtrace: [] kmalloc include/linux/slab.h:581 [inline] [] kzalloc include/linux/slab.h:714 [inline] [] keyctl_watch_key+0xec/0x2e0 security/keys/keyctl.c:1800 [] __do_sys_keyctl+0x3c4/0x490 security/keys/keyctl.c:2016 [] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 [] entry_SYSCALL_64_after_hwframe+0x44/0xae"
}
],
"lastModified": "2026-06-17T05:17:31.510",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "552AD555-63DB-4D57-BBAA-86EA26658508",
"versionEndExcluding": "5.10.110",
"versionStartIncluding": "5.8"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "27C42AE8-B387-43E2-938A-E1C8B40BE6D5",
"versionEndExcluding": "5.15.33",
"versionStartIncluding": "5.11"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "20C43679-0439-405A-B97F-685BEE50613B",
"versionEndExcluding": "5.16.19",
"versionStartIncluding": "5.16"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "210C679C-CF84-44A3-8939-E629C87E54BF",
"versionEndExcluding": "5.17.2",
"versionStartIncluding": "5.17"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}