CVE-2026-89524: Linux kernel · wifi: ath6kl: clamp assoc request/response lengths before subtracting IE offsets
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.1 High.
Data as of 28 Oct 2026, 01:01 UTC
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.
References
- ubuntu.com/security/CVE-2026-89524 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89524 (opens in a new tab)
- git.kernel.org/linus/3bbd05723d15dd06f0560bcd94fbf9a91b5f5613 (opens in a new tab)
- git.kernel.org/stable/c/3bbd05723d15dd06f0560bcd94fbf9a91b5f5613 (opens in a new tab)
- git.kernel.org/stable/c/8eb73016fb3968cf2db3987a92764563a3af773a (opens in a new tab)
- git.kernel.org/stable/c/e1330d719c047c4d8190a16be034b29fc601a815 (opens in a new tab)
- git.kernel.org/stable/c/e3619bed5da125713b29ac881dc66f5e06606f88 (opens in a new tab)