CVE-2026-33810
High
Description
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.
SeverityHigh
CVSS8.2
Exploit probability—
ProductGo
PublishedApr 8, 2026
First seenApr 8, 2026
Weakness typeCWE-295CWE-295
How to fix
Update
- golang go1.26.2 or later
- stdlib1.26.2 or later
Vendor advisories
- access.redhat.com/errata/RHSA-2026:68334
- access.redhat.com/errata/RHSA-2026:54757
- access.redhat.com/errata/RHSA-2026:14391
- access.redhat.com/errata/RHSA-2026:36796
- access.redhat.com/errata/RHSA-2026:28047
- access.redhat.com/errata/RHSA-2026:39810
- access.redhat.com/errata/RHSA-2026:34365
- access.redhat.com/errata/RHSA-2026:49703
- access.redhat.com/errata/RHSA-2026:67149
- access.redhat.com/errata/RHSA-2026:49702
- access.redhat.com/errata/RHSA-2026:67517
- access.redhat.com/errata/RHSA-2026:56143
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| golang go | 1.26.0 ≤ v < 1.26.2 | 1.26.2 |
| stdlibGo | 1.26.0-0 ≤ v < 1.26.2 | 1.26.2 |
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