CVE-2026-93785

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux21fed0d5b763b94a7d1568c27d0cce892ab8d43e < eeac976b74b4f697cfc517187b7cbfd72652dbbcaffected
LinuxLinux21fed0d5b763b94a7d1568c27d0cce892ab8d43e < 125b05ac8ca8758950e4369c1542d57a162f504caffected
LinuxLinux21fed0d5b763b94a7d1568c27d0cce892ab8d43e < 945f6cde6bcf8f08f6fa5df8882b1b9582e55efaaffected
LinuxLinux21fed0d5b763b94a7d1568c27d0cce892ab8d43e < 3a4a34a732e8a08309eed0a74314dbd9f2f1c972affected
LinuxLinux21fed0d5b763b94a7d1568c27d0cce892ab8d43e < 6cfeef221ac00d63c07f6122f58e6159bde69ca0affected
LinuxLinux21fed0d5b763b94a7d1568c27d0cce892ab8d43e < 8b12f65d7caf16d124098cb4895a203367d35b57affected
LinuxLinux21fed0d5b763b94a7d1568c27d0cce892ab8d43e < 455488cd5054bcc59db40fa1cc2c004031a5b2a5affected
LinuxLinux3.2affected
LinuxLinux0 < 3.2unaffected
LinuxLinux5.10.271 <= 5.10.*unaffected
LinuxLinux5.15.222 <= 5.15.*unaffected
LinuxLinux6.1.189 <= 6.1.*unaffected
LinuxLinux6.6.158 <= 6.6.*unaffected
LinuxLinux6.12.111 <= 6.12.*unaffected
LinuxLinux6.18.53 <= 6.18.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References