CVE-2026-93079 PUBLISHED

cxl/features: Reject Get Feature count larger than the output buffer

Assigner: Linux
Reserved: 17.09.2026 Published: 17.09.2026 Updated: 17.09.2026

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

cxl/features: Reject Get Feature count larger than the output buffer

cxlctl_get_feature() sizes its output buffer from the user's fwctl_rpc.out_len, but the device is told to write cxl_mbox_get_feat_in.count bytes into rpc_out->payload, which is a separate user-controlled value. Nothing bounds count against out_len, so a small out_len with a large count overflows the kvzalloc()'d buffer. A heap OOB write reachable from FWCTL_RPC.

Reject requests where count exceeds the available payload room, before allocating.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 5908f3ed6dc209e5c824e63afda7545805f75a7e to 3f02031a0a53de0d3ef066c92d0486b2b11be40c (excl.)
  • affected from 5908f3ed6dc209e5c824e63afda7545805f75a7e to 329ea475581c647a680a6937e353c1a6e2534b40 (excl.)
  • affected from 5908f3ed6dc209e5c824e63afda7545805f75a7e to 4bf6bac375076ced2fa4b3fef8739bd985f93456 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 6.15 is affected
  • unaffected from 0 to 6.15 (excl.)
  • unaffected from 6.18.52 to 6.18.* (incl.)
  • unaffected from 7.2.6 to 7.2.* (incl.)
  • unaffected from 7.3-rc1 to * (incl.)

References