CVE-2025-38737 (GCVE-0-2025-38737)
Vulnerability from cvelistv5
Published
2025-09-05 17:20
Modified
2026-08-05 12:04
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix oops due to uninitialised variable
Fix smb3_init_transform_rq() to initialise buffer to NULL before calling
netfs_alloc_folioq_buffer() as netfs assumes it can append to the buffer it
is given. Setting it to NULL means it should start a fresh buffer, but the
value is currently undefined.
References
Impacted products
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"fs/smb/client/smb2ops.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "4931fe2dbe1cc0e7d350a4b51b0b330e43971d98",
"status": "affected",
"version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
"versionType": "git"
},
{
"lessThan": "6adaa9fae36f848afa7278945d725e197e33c496",
"status": "affected",
"version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
"versionType": "git"
},
{
"lessThan": "453a6d2a68e54a483d67233c6e1e24c4095ee4be",
"status": "affected",
"version": "a2906d3316fc19bf0ade84618bb73eab604c447e",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"fs/smb/client/smb2ops.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.12"
},
{
"lessThan": "6.12",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.44",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.16.*",
"status": "unaffected",
"version": "6.16.4",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.44",
"versionStartIncluding": "6.12",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.16.4",
"versionStartIncluding": "6.12",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.17",
"versionStartIncluding": "6.12",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: Fix oops due to uninitialised variable\n\nFix smb3_init_transform_rq() to initialise buffer to NULL before calling\nnetfs_alloc_folioq_buffer() as netfs assumes it can append to the buffer it\nis given. Setting it to NULL means it should start a fresh buffer, but the\nvalue is currently undefined."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:N - The vulnerable path is the SMB3 client transport-encryption routine, and whether it is entered is dictated by server-supplied SESSION_SETUP/TREE_CONNECT flags (SMB2_SESSION_FLAG_ENCRYPT_DATA / SHI1005_FLAGS_ENCRYPT_DATA), so a remote or MITM SMB server across the network selects the vulnerable path and receives the leaked plaintext of the corrupted buffer.\nAC:L - Once encryption is negotiated, every write with a payload runs the uninitialised pointer through netfs_alloc_folioq_buffer(); the stack slot is reachable and groomable via ordinary syscall sequences on the writing task\u0027s kernel stack, with no condition outside the attacker\u0027s influence.\nPR:N - The remote SMB server presents no credentials to the client and needs none to set the encryption flags that gate the path; on the local side, any user holding a normal write handle to the mounted share triggers it with no elevated privileges.\nUI:N - An already-mounted share reaches the path through routine writeback and automatic reconnect (which re-runs session setup and tree connect), so no victim action beyond normal use of an existing mount is required.\nS:U - The wild reads, writes and bogus folio_put()s all occur within the kernel\u0027s own memory and the same security authority; no VM, IOMMU or sandbox boundary is crossed.\nC:H - Because *_buffer is never reassigned, the garbage folio_queue is used as the ITER_SOURCE for crypt_message(), so arbitrary kernel memory pointed to by the stale chain is encrypted and sent to the remote peer, and freeing the chain yields further use-after-free read primitives.\nI:H - netfs_alloc_folioq_buffer() writes through the garbage pointer (tail-\u003enext = p, p-\u003eprev = tail, folioq_append_mark()), and cifs_copy_iter_to_folioq() then copies attacker-supplied write() data into folios derived from that chain, giving a content-controlled kernel write suitable for control-flow hijacking.\nA:H - The commit is titled \"Fix oops due to uninitialised variable\" \u2014 dereferencing the indeterminate pointer oopses the kernel, and the resulting folio_queue/folio refcount corruption and bogus frees cause further panics."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-05T12:04:26.998Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/4931fe2dbe1cc0e7d350a4b51b0b330e43971d98"
},
{
"url": "https://git.kernel.org/stable/c/6adaa9fae36f848afa7278945d725e197e33c496"
},
{
"url": "https://git.kernel.org/stable/c/453a6d2a68e54a483d67233c6e1e24c4095ee4be"
}
],
"title": "cifs: Fix oops due to uninitialised variable",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2025-38737",
"datePublished": "2025-09-05T17:20:37.719Z",
"dateReserved": "2025-04-16T04:51:24.034Z",
"dateUpdated": "2026-08-05T12:04:26.998Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…