CVE-2026-12236: zephyrproject zephyr · Dos
Affects zephyrproject zephyrSource CVE Database V5
Not known to be exploited · CVSS 6.5 Medium : upgrade to 4.4.2 or 4.3.2 when convenient.
Data as of 11 Nov 2026, 23:24 UTC
Thin evidence
One scorer or none| CNA (zephyr) | CVSS 3.1 | 6.5 |
|---|
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.4.2, 4.3.2
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 11 Nov 2026.
What to do
Upgrade zephyrproject zephyr to 4.4.2 or 4.3.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| zephyrprojectzephyr | Affected
| Fixed in
|
| zephyrprojectzephyr | Affected
| Fixed in
|
GitHubzephyrpkg:github/zephyrOther 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
This vulnerability is fixed in Zephyr versions 4.3.2 and 4.4.2. Users should upgrade to these or later versions to remediate the issue. No additional mitigation is required as the fix properly validates the response length to prevent infinite loops.
Description
CVE-2026-12236 is a denial of service vulnerability in the Zephyr Bluetooth host GATT client. It occurs in the parse_read_std_char_desc() function when processing a malicious ATT Read By Type Response with a zero-length entry. This causes an infinite loop that hangs the Bluetooth host processing thread, leading to a denial of service. The flaw can be triggered by any connected peer during standard descriptor discovery without requiring authentication. The issue is fixed in Zephyr versions 4.3.2 and 4.4.2.