wifi: mt76: mt7921/mt7925: fix NULL dereference in CSA beacon (CVE-2026-64325) | HOL Guard CVE

Medium · CVSS 5.5CVE-2026-64325

wifi: mt76: mt7921/mt7925: fix NULL dereference in CSA beacon

Answer in brief

CVE-2026-64325 records a Medium severity (CVSS 5.5) vulnerability in wifi: mt76: mt7921/mt7925: fix NULL dereference in CSA beacon. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jul 25, 2026Updated Sep 4, 2026Source checked Oct 1, 2026First seen by HOL Aug 11, 2026Material review Sep 4, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 5.5
Exploitation: Not marked as known exploited
Affected software: 3 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
Product	Affected versions	Fixed versions
cpe:2.3:o:linux:linux_kernel::::::::	Not reported	Not reported

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=8aa2f59260eb66fc80378c158922ccb741ccc491 <77e7b127472a191e086e1e0b1b051703f33b1801 \|\| >=8aa2f59260eb66fc80378c158922ccb741ccc491 <351dd7d2c80d23e56dcce6faa4e62bea5b0877c7	77e7b127472a191e086e1e0b1b051703f33b1801, 351dd7d2c80d23e56dcce6faa4e62bea5b0877c7
Linux/Linuxgeneric	6.14	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 77e7b127472a191e086e1e0b1b051703f33b1801 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jul 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 4, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7921/mt7925: fix NULL dereference in CSA beacon This patch is based on a BUG as reported by Bongani Hlope at https://lore.kernel.org/all/[email protected]/ When a channel-switch announcement (CSA) beacon is received, cfg80211 queues a wiphy work item that eventually calls mt7921_channel_switch_rx_beacon(). If the station disconnects (or the channel context is otherwise torn down) between the time the work is queued and the time it runs, the driver's dev->new_ctx pointer can already have been cleared to NULL. mt7921_channel_switch_rx_beacon() then dereferences new_ctx unconditionally, triggering a NULL pointer dereference at address 0x0: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:mt7921_channel_switch_rx_beacon+0x1f/0x100 [mt7921_common] The same missing guard exists in mt7925_channel_switch_rx_beacon(), which shares the same code pattern introduced by the same commit. Add an early-return NULL check for dev->new_ctx in both mt7921_channel_switch_rx_beacon() and mt7925_channel_switch_rx_beacon(). When new_ctx is NULL there is no pending channel switch to process, so returning immediately is the correct and safe action. Oops-Analysis: http://oops.fenrus.org/reports/lkml/[email protected]/report.html

Quoted source text, attributed separately from HOL analysis.