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

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.

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Meta Information

Published
2026-09-11
Last Modified
2026-09-11
Generated
2026-09-12
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
linux linux_kernel *

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-UNKNOWN

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