CVE-2026-33810
Published:April 08, 2026
Updated:April 20, 2026
When verifying a certificate chain containing excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs which use a different case than the constraint. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.
Affected Packages
https://github.com/golang/go.git (GITHUB):
Affected version(s) >=go1 <go1.25.9Fix Suggestion:
Update to version go1.25.9https://github.com/golang/go.git (GITHUB):
Affected version(s) >=go1.26.0 <go1.26.2Fix Suggestion:
Update to version go1.26.2github.com/golang/go (GO):
Affected version(s) >=go1.26.0 <go1.26.2Fix Suggestion:
Update to version go1.26.2github.com/golang/go (GO):
Affected version(s) >=go1 <go1.25.9Fix Suggestion:
Update to version go1.25.9Related Resources (6)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Improper Certificate Validation
EPSS
Base Score:
0.01
