CVE-2026-64255 PUBLISHED

wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers

Assigner: Linux
Reserved: 19.07.2026 Published: 24.07.2026 Updated: 24.07.2026

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

wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers

Three BA session handlers use ffs(ba_data->sta_mask) - 1 to derive a station ID without checking that sta_mask is non-zero. When sta_mask is zero, ffs() returns 0 and the subtraction wraps to 0xFFFFFFFF, causing an out-of-bounds access on fw_id_to_link_sta[].

Add WARN_ON_ONCE(!ba_data->sta_mask) guards before each ffs() call, consistent with the existing check in iwl_mld_ampdu_rx_start().

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 1de92789ce31e46fa7e7d8e89c90b19cdb1c103b (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to fe7f339f63c9dc4ca546ed7ac38ba4bb3a99dcfc (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to f056fc2b927448d37eca6b6cacc3d1b0f67b20d2 (excl.)
  • affected from 0 to 6.18.38 (excl.)
  • affected from 0 to 7.1.3 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • unaffected from 6.18.38 to 6.18.* (incl.)
  • unaffected from 7.1.3 to 7.1.* (incl.)
  • unaffected from 7.2-rc1 to * (incl.)

References