smb: client: fix next_buffer UAF and NextCommand bounds in compound PDUs
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix next_buffer UAF and NextCommand bounds in compound PDUs Fix several related bounds checking and pointer lifecycle issues in receive_encrypted_standard()'s handling of compound encrypted frames: - Clear next_buffer after assigning it to server->bigbuf. A stale next_buffer pointer can lead to a use-after-free on subsequent error paths. - Update pdu_length to the decrypted plaintext size (buf_size). Using the pre-decryption length allows NextCommand to point into stale ciphertext residue. - Reject next_cmd values smaller than MID_HEADER_SIZE(server). - Fix an integer overflow in the upper bound check by verifying pdu_length - next_cmd < MID_HEADER_SIZE(server), ensuring the trailing slice is large enough for a header.
CVE-2026-98171
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98171
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
"lessThan": "72eaef1f37a3b6bec11c342736834dc3707be3e4",
"versionType": "git"
},
{
"status": "affected",
"version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
"lessThan": "491e33144dee872cffda207f6fcb09260728f803",
"versionType": "git"
},
{
"status": "affected",
"version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
"lessThan": "8749946579708ea0d339034bb7f423a67dbe89cf",
"versionType": "git"
},
{
"status": "affected",
"version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
"lessThan": "96c436e4b010711452b2872558938f4ef276492a",
"versionType": "git"
},
{
"status": "affected",
"version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
"lessThan": "858d5ac22cb889266993e7670f9f0c4f4aeedd78",
"versionType": "git"
},
{
"status": "affected",
"version": "b24df3e30cbf48255db866720fb71f14bf9d2f39",
"lessThan": "05762c5bc1cfdcac36747994fde2c04387a457f1",
"versionType": "git"
}
],
"programFiles": [
"fs/smb/client/smb2ops.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.19"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.19",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.189",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.54",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.8",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/smb/client/smb2ops.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98171
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #38256 · Revision 1
- Added to Heist Feed
- Publisher date