CVE-2026-6731

EUVD-2026-39555
X.509 name constraint bypass via the Subject Common Name when treated as a DNS-type name. A certificate whose Subject CN violates an issuing CA's DNS name constraints could be accepted.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 2.51%
Affected Products (NVD)
VendorProductVersion
wolfsslwolfssl
3.9.10 ≤
𝑥
< 5.9.2
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
wolfssl
bookworm
vulnerable
bookworm (security)
5.5.4-2+deb12u3
fixed
bullseye
postponed
sid
5.9.2-1
fixed
trixie
no-dsa
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
wolfssl
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
questing
ignored
resolute
needs-triage
Common Weakness Enumeration
References
https://github.com/wolfSSL/wolfssl/pull/10223
https://www.wolfssl.com/docs/security-vulnerabilities/