CVE-2026-89524
Received
Received - Intake
Buffer Underflow in Linux Kernel WiFi ath6kl Driver
Vulnerability report for CVE-2026-89524, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-11
Last updated on: 2026-09-11
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath6kl: clamp assoc request/response lengths before subtracting IE offsets
ath6kl_cfg80211_connect_event() subtracts fixed IE offsets from
assoc_req_len (-= 4) and assoc_resp_len (-= 6), both u8, with no lower
bound. The aggregate check recently added to ath6kl_wmi_connect_event_rx()
bounds the declared lengths from above (their sum must fit the received
event), but an assoc request/response shorter than its fixed offset still
underflows here: the u8 wraps to ~250, and cfg80211_connect_result() /
cfg80211_roamed() then treat that wrapped value as the IE length and copy
that many bytes out of the small assoc_info buffer to user space via
nl80211, disclosing adjacent slab memory.
Clamp both lengths to their offsets before subtracting.
Found by 0sec (https://0sec.ai) using automated source analysis; the
missing lower bound is evident from source. Compile-tested.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |