CVE-2026-64539: Linux kernel · Bluetooth: eir: Fix stack OOB write when prepending the Flags AD
Source GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in f1b4df9c260c51726da2e86e19322825fddeefd0 : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 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 – fixed in f1b4df9c260c51726da2e86e19322825fddeefd0, 9174992ee1045c9c96e53eecda64f49dd7e8fbba, 57077eeb586c42f124bc09e018449362223067b3 +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Jul 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
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
AI-suggested
The vulnerability has been resolved in the Linux kernel source, so applying the latest kernel updates when available is recommended. Until then, restrict CAP_NET_ADMIN privileges to trusted users and avoid using LE-only controllers with legacy advertising paths if possible.
Description
A stack out-of-bounds write vulnerability in the Linux kernel's Bluetooth EIR advertising data handling was resolved. The issue occurs when the kernel prepends a 3-byte Flags AD structure to advertising data without properly checking buffer boundaries, leading to a potential overflow. This vulnerability is reachable by a local user with CAP_NET_ADMIN privileges on an LE-only controller using the legacy advertising path.
References
- nvd.nist.gov/vuln/detail/CVE-2026-64539 (opens in a new tab)
- git.kernel.org/stable/c/09301f1fdf2aef8cce34d0c4650c30e7edb1ced9 (opens in a new tab)
- git.kernel.org/stable/c/0f0b6232af56441d0a2dcb173cc4f8d8aab39014 (opens in a new tab)
- git.kernel.org/stable/c/57077eeb586c42f124bc09e018449362223067b3 (opens in a new tab)
- git.kernel.org/stable/c/6f5fb689fdf80bdd143f22a502f9eb1f3c85e286 (opens in a new tab)
- git.kernel.org/stable/c/f1b4df9c260c51726da2e86e19322825fddeefd0 (opens in a new tab)