VulnerabilityPublished 25 Sep 2026Updated 30 Oct 2026

CVE-2026-97561: Linux kernel · smb: client: honor forceuid/forcegid when mapping SIDs to uid/gid

Source GCVE Database

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Authoritative record:CVE-2026-97561· Medium

Not known to be exploited · fixed in e1b74f8f8c1d13190b09fe623b729d36b7ac22a8 : update Linux kernel when convenient.

Data as of 30 Oct 2026, 17:33 UTC

Severity

Medium

Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD

Thin evidence

One scorer or none

Patch: Available – fixed in e1b74f8f8c1d13190b09fe623b729d36b7ac22a8, be6eccccec867c22d7c65fab4ea4e91ec3d5b8c6, bc35de451c128d399ad185d6269f8847e97cd1c9 +3

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-vg8h-339p-69c7

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 9409ae58e0759d010b347e7b19ebc90ab5d4b98f, < e1b74f8f8c1d13190b09fe623b729d36b7ac22a8	Fixed in e1b74f8f8c1d13190b09fe623b729d36b7ac22a8
LinuxLinux	Affected ≥ 9409ae58e0759d010b347e7b19ebc90ab5d4b98f, < be6eccccec867c22d7c65fab4ea4e91ec3d5b8c6	Fixed in be6eccccec867c22d7c65fab4ea4e91ec3d5b8c6
LinuxLinux	Affected ≥ 9409ae58e0759d010b347e7b19ebc90ab5d4b98f, < bc35de451c128d399ad185d6269f8847e97cd1c9	Fixed in bc35de451c128d399ad185d6269f8847e97cd1c9
LinuxLinux	Affected ≥ 9409ae58e0759d010b347e7b19ebc90ab5d4b98f, < 89a3b4704af2208e381c55037ff2d1e2365b83e4	Fixed in 89a3b4704af2208e381c55037ff2d1e2365b83e4
LinuxLinux	Affected ≥ 9409ae58e0759d010b347e7b19ebc90ab5d4b98f, < 18a72975e9f35aadecc75b031f693f2d1f49308f	Fixed in 18a72975e9f35aadecc75b031f693f2d1f49308f
LinuxLinux	Affected ≥ 9409ae58e0759d010b347e7b19ebc90ab5d4b98f, < 6ac7a29691558bed18e2df1780636b8aa0fd13d5	Fixed in 6ac7a29691558bed18e2df1780636b8aa0fd13d5

AI-suggested

A fix has been implemented in the Linux kernel to ensure that the forceuid and forcegid mount options are honored consistently. Administrators should update to the fixed kernel version once available to prevent untrusted SMB servers from overriding local ownership settings.

Description

A vulnerability in the Linux kernel SMB client allowed an untrusted server to override local file ownership despite mount options specifying forced user and group IDs. This occurred because certain code paths ignored the forceuid/forcegid mount options and used server-provided ownership values. The issue has been fixed by ensuring these code paths respect the forced UID/GID settings.

Impact

An untrusted SMB server could cause local files to appear owned by arbitrary users or groups, ignoring administrator-specified forced ownership settings. This could lead to confusion or potential privilege issues in environments relying on forced UID/GID mappings for access control consistency.

Summary

CVE-2026-97561 addresses a flaw in the Linux kernel SMB client where the forceuid and forcegid mount options, intended to enforce specific local user and group ownership, were bypassed by several code paths that unconditionally mapped server SIDs to local UID/GID values. Specifically, smb311_posix_info_to_fattr(), cifs_posix_to_fattr(), and parse_sec_desc() functions overwrote the forced ownership settings with server-provided values. The fix involves adding checks for CIFS_MOUNT_OVERR_UID and CIFS_MOUNT_OVERR_GID flags before calling sid_to_id(), aligning with existing handling in cifs_unix_basic_to_fattr().

References

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