CVE-2026-93785

cifs: validate idmap key payload length

State: Published
Severity: Not scored
Published: Sep 24, 2026
Updated: Oct 3, 2026
Reserved: Sep 18, 2026

Description

In the Linux kernel, the following vulnerability has been resolved:

cifs: validate idmap key payload length

The cifs.idmap key type stores its payload length in key->datalen, which is limited to U16_MAX. Accepting a larger key payload truncates the recorded length and can make later users interpret the payload using inconsistent bounds.

Reject oversized preparsed payloads before allocating or copying them. This keeps key->datalen consistent with the stored data for both inline and separately allocated idmap payloads.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before eeac976b74b4f697cfc517187b7cbfd72652dbbcAffected 21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 125b05ac8ca8758950e4369c1542d57a162f504cAffected 21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 945f6cde6bcf8f08f6fa5df8882b1b9582e55efaAffected 21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 3a4a34a732e8a08309eed0a74314dbd9f2f1c972Affected 21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 6cfeef221ac00d63c07f6122f58e6159bde69ca0Affected 21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 8b12f65d7caf16d124098cb4895a203367d35b57Affected 21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 455488cd5054bcc59db40fa1cc2c004031a5b2a5Affected
LinuxLinux	3.2Affected before 3.2Not affected 5.10.271 through 5.10.Not affected 5.15.222 through 5.15.Not affected 6.1.189 through 6.1.Not affected 6.6.158 through 6.6.Not affected 6.12.111 through 6.12.Not affected 6.18.53 through 6.18.Not affected 7.2 and laterNot affected

Product

Versions

LinuxLinux

21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before eeac976b74b4f697cfc517187b7cbfd72652dbbcAffected
21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 125b05ac8ca8758950e4369c1542d57a162f504cAffected
21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 945f6cde6bcf8f08f6fa5df8882b1b9582e55efaAffected
21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 3a4a34a732e8a08309eed0a74314dbd9f2f1c972Affected
21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 6cfeef221ac00d63c07f6122f58e6159bde69ca0Affected
21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 8b12f65d7caf16d124098cb4895a203367d35b57Affected
21fed0d5b763b94a7d1568c27d0cce892ab8d43e to before 455488cd5054bcc59db40fa1cc2c004031a5b2a5Affected

LinuxLinux

3.2Affected
before 3.2Not affected
5.10.271 through 5.10.*Not affected
5.15.222 through 5.15.*Not affected
6.1.189 through 6.1.*Not affected
6.6.158 through 6.6.*Not affected
6.12.111 through 6.12.*Not affected
6.18.53 through 6.18.*Not affected
7.2 and laterNot affected

References

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