CVE-2026-46140: Linux kernel · Bluetooth: btmtk: validate WMT event SKB length before struct access
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High · patch available : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 28 May 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@7.0.0-28.28?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@7.0.0-1009.9?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke@7.0.0-1003.4?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.
AI-suggested
An official patch is available and should be applied to affected Linux kernel versions. The vendor advisory from Ubuntu confirms that this issue is fixed in updated kernel releases. Users should update to the fixed kernel versions to mitigate this vulnerability. No additional mitigations are required beyond applying the official fix.
Description
A vulnerability in the Linux kernel Bluetooth driver btmtk was resolved that involved improper validation of WMT event SKB length before accessing certain structures. This flaw could cause out-of-bounds reads from the SKB tailroom due to short firmware responses. The issue was fixed by validating and advancing past the base WMT event header before accessing data fields. The vulnerability affects multiple Linux kernel versions prior to 7.0.0-28.28 and specific earlier versions. A patch is available to address this issue.
References
- ubuntu.com/security/CVE-2026-46140 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-46140 (opens in a new tab)
- git.kernel.org/linus/634a4408c0615c523cf7531790f4f14a422b9206 (opens in a new tab)
- git.kernel.org/stable/c/624fb79dadc1b65757986a9d0fdde5c0cf3fe179 (opens in a new tab)
- git.kernel.org/stable/c/634a4408c0615c523cf7531790f4f14a422b9206 (opens in a new tab)
- git.kernel.org/stable/c/70d37a8b9229e394cc17ddad47e90b81d80fcd09 (opens in a new tab)
- git.kernel.org/stable/c/c411cf1bfde951cfa821809cf4020ba177f76e0c (opens in a new tab)
- ubuntu.com/security/notices/USN-8566-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8568-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8569-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8603-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8618-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8663-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8664-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)