CVE-2026-71226: Stephan Muelle libkcapi · Use After Free
Affects Stephan Muelle libkcapiSource CVE Database V5
Not known to be exploited · CVSS 7.3 High : upgrade to 1.5.1 soon.
Data as of 3 Nov 2026, 11:11 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 7.3 |
|---|
- 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 1.5.1
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:HExploitation evidence
Disclosed: evidence found.
CVE published 5 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 3 Nov 2026.
What to do
Upgrade Stephan Muelle libkcapi to 1.5.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Stephan Muellelibkcapi | Affected
| Fixed in
|
GitHublibkcapipkg:github/libkcapiOther 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
To mitigate this vulnerability, applications should avoid initializing libkcapi handles with the KCAPI_INIT_AIO flag and prefer synchronous interfaces. If the one-shot AIO path must be used, applications must ensure that output buffers (outiov) are not freed or reused immediately after an error return, allowing all kernel completions to complete before buffer reuse or release. This operational mitigation prevents delayed kernel writes into freed or reallocated memory.
Description
Memory Corruption via Uncanceled AIO Requests on Error: libkcapi's one-shot AIO path can return an error before all submitted IOCBs are drained, allowing later kernel writes into caller-owned output buffers.
References
- access.redhat.com/security/cve/CVE-2026-71226 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2462114 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:56985 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:67266 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:67265 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:67267 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:69285 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:87712 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:93453 (opens in a new tab)