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
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6cfeef221ac00d63c07f6122f58e6159bde69ca0affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8b12f65d7caf16d124098cb4895a203367d35b57affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 455488cd5054bcc59db40fa1cc2c004031a5b2a5affected
LinuxLinux0 < 6.12.111affected
LinuxLinux0 < 6.18.53affected
LinuxLinux6.12.111 <= 6.12.*unaffected
LinuxLinux6.18.53 <= 6.18.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References