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

wifi: mac80211: minstrel_ht: validate fixed rate index

The fixed_rate_idx debugfs file is a plain u32 attribute, so any value
can be written to it. minstrel_ht_update_stats() then copies the value
into mi->max_tp_rate[] and mi->max_prob_rate, and
minstrel_ht_set_rate() uses MI_RATE_GROUP()/MI_RATE_IDX() to index
minstrel_mcs_groups[] (42 entries) and mi->groups[].rates[] (10 entries)
with it.

Writing e.g. 65535 selects group 4095 and rate index 15, far outside
both arrays. The out-of-bounds entries are dereferenced and updated as
struct minstrel_rate_stats (retry counts, etc.), so the invalid index
corrupts adjacent kernel memory. With CONFIG_UBSAN_BOUNDS the access is
reported as an array-index-out-of-bounds in minstrel_ht_set_rate().

Only a valid group/rate pair, or U32_MAX to disable fixed rate
processing, can be used safely, so reject any other value when the
debugfs file is written.

The file is only reachable through a root-only debugfs mount, so this is
not a privilege boundary. The out-of-bounds access is still a bug that
must not be reachable through a writable debugfs attribute.
Published: 2026-10-18
Score: n/a
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Sun, 18 Oct 2026 16:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: minstrel_ht: validate fixed rate index The fixed_rate_idx debugfs file is a plain u32 attribute, so any value can be written to it. minstrel_ht_update_stats() then copies the value into mi->max_tp_rate[] and mi->max_prob_rate, and minstrel_ht_set_rate() uses MI_RATE_GROUP()/MI_RATE_IDX() to index minstrel_mcs_groups[] (42 entries) and mi->groups[].rates[] (10 entries) with it. Writing e.g. 65535 selects group 4095 and rate index 15, far outside both arrays. The out-of-bounds entries are dereferenced and updated as struct minstrel_rate_stats (retry counts, etc.), so the invalid index corrupts adjacent kernel memory. With CONFIG_UBSAN_BOUNDS the access is reported as an array-index-out-of-bounds in minstrel_ht_set_rate(). Only a valid group/rate pair, or U32_MAX to disable fixed rate processing, can be used safely, so reject any other value when the debugfs file is written. The file is only reachable through a root-only debugfs mount, so this is not a privilege boundary. The out-of-bounds access is still a bug that must not be reachable through a writable debugfs attribute.
Title wifi: mac80211: minstrel_ht: validate fixed rate index
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-18T15:46:33.395Z

Reserved: 2026-09-25T10:25:14.365Z

Link: CVE-2026-98703

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-18T16:17:23.810

Modified: 2026-10-18T16:17:23.810

Link: CVE-2026-98703

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.