CVE-2026-95210
GnuTLS v3.8.13 does not reject a critical keyUsage extension when it cannot be processed, such as when extnValue is an ASN.1 NULL (05 00) instead of a BIT STRING. NOTE: the Supplie
What happened?
GnuTLS v3.8.13 does not reject a critical keyUsage extension when it cannot be processed, such as when extnValue is an ASN.1 NULL (05 00) instead of a BIT STRING. NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
Affected software and versions
| Software | Version information | Fixed version |
|---|---|---|
| n/an/a | affected: n/a | See vendor advisory |
Version information comes from the source record and can include unaffected products and exceptions. Distribution packages may contain backported fixes: an older upstream version alone does not prove a server is affected.
Is it being exploited?
This CVE was not listed in the CISA catalogue at our last retrieval. This does not establish that exploitation is absent.
How to respond
- Confirm the product, installed package version, and any configuration requirements in the vendor advisory.
- Follow the vendor’s remediation or workaround guidance in the references below. Structured fixed-version data is unavailable here; the publisher’s description may include a fix or workaround.
- Restart affected services if required, then verify the running version. Known exploitation may warrant investigation as well as patching.
Sources and remediation references
- https://www.cve.org/CVERecord?id=CVE-2026-95210
- http://gnutls.com
- https://gist.github.com/lkloliver/4aad23689202720c4068f43b3c6069c7
- https://gitlab.com/gnutls/gnutls/-/work_items/1965
- https://gitlab.com/gnutls/gnutls/-/blob/e2169a87c7fb91935c2845088204b102baed4c5f/SECURITY.md
- https://github.com/lkloliver/poc/tree/main/CVE-2026-95210