CVE-2026-6091
Partial-chain verification accepts untrusted intermediate as trust anchor
Description
Partial-chain certificate verification may accept chains that terminate at a peer-supplied, untrusted intermediate certificate rather than a trusted anchor. An attacker could present a chain that ends at an intermediate they control and have it accepted as valid. This affects the OpenSSL compatibility certificate-path-building path (wolfSSL_X509_verify_cert / X509_STORE, OPENSSL_EXTRA) when the X509_V_FLAG_PARTIAL_CHAIN verify flag is enabled.
INFO
Published Date :
June 25, 2026, 4:46 p.m.
Last Modified :
June 25, 2026, 4:46 p.m.
Remotely Exploit :
Yes !
Source :
wolfSSL
Affected Products
The following products are affected by CVE-2026-6091
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | 50d2cd11-d01a-48ed-9441-5bfce9d63b27 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Disable X509_V_FLAG_PARTIAL_CHAIN flag.
- Update OpenSSL compatibility library to a patched version.
- Ensure chains terminate at trusted anchors.
- Verify certificate chain integrity.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-6091 vulnerability anywhere in the article.