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.
Metrics
CVSS 3.1 8.2/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:NWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Go standard library | crypto/x509 | >= 1.26.0-0, < 1.26.2 |
| Red Hat | Cryostat 4 on RHEL 9 | — |
| Red Hat | HawtIO HawtIO 4.4.0 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9 | — |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — |
| Red Hat | Red Hat OpenStack Platform 16.2 | — |
| Red Hat | Red Hat OpenStack Platform 16.2 | — |
| Red Hat | Red Hat OpenStack Platform 17.1 for RHEL 9 | — |
| Red Hat | Red Hat OpenStack Services on OpenShift 18.0 | — |
| Red Hat | Red Hat Satellite 6.19 for RHEL 9 | — |
| Red Hat | RHEM 1.0 for RHEL 9 | — |
| Red Hat | RHEM 1.1 for RHEL 10 | — |
| Red Hat | RHEM 1.1 for RHEL 9 | — |
References
- https://go.dev/cl/763763Patch
- https://go.dev/issue/78332Issue Tracking
- https://groups.google.com/g/golang-announce/c/0uYbvbPZRWUMailing List, Release Notes
- https://pkg.go.dev/vuln/GO-2026-4866Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/04/19/4
- http://www.openwall.com/lists/oss-security/2026/04/20/1
- https://access.redhat.com/errata/RHSA-2026:10155
- https://access.redhat.com/errata/RHSA-2026:10158
- https://access.redhat.com/errata/RHSA-2026:13545
- https://access.redhat.com/errata/RHSA-2026:14391
- https://access.redhat.com/errata/RHSA-2026:19135
- https://access.redhat.com/errata/RHSA-2026:19144
- https://access.redhat.com/errata/RHSA-2026:19353
- https://access.redhat.com/errata/RHSA-2026:19714
- https://access.redhat.com/errata/RHSA-2026:19719
- https://access.redhat.com/errata/RHSA-2026:19720
- https://access.redhat.com/errata/RHSA-2026:19721
- https://access.redhat.com/errata/RHSA-2026:21769
- https://access.redhat.com/errata/RHSA-2026:21772
- https://access.redhat.com/errata/RHSA-2026:22347
- https://access.redhat.com/errata/RHSA-2026:22485
- https://access.redhat.com/errata/RHSA-2026:22862
- https://access.redhat.com/errata/RHSA-2026:22958
- https://access.redhat.com/errata/RHSA-2026:22959
- https://access.redhat.com/errata/RHSA-2026:22960
- https://access.redhat.com/errata/RHSA-2026:22961
- https://access.redhat.com/errata/RHSA-2026:22962
- https://access.redhat.com/errata/RHSA-2026:23345
- https://access.redhat.com/errata/RHSA-2026:24478
- https://access.redhat.com/errata/RHSA-2026:25089
- https://access.redhat.com/errata/RHSA-2026:26568
- https://access.redhat.com/errata/RHSA-2026:26571
- https://access.redhat.com/errata/RHSA-2026:26585
- https://access.redhat.com/errata/RHSA-2026:28047
- https://access.redhat.com/errata/RHSA-2026:29854
- https://access.redhat.com/errata/RHSA-2026:34192
- https://access.redhat.com/errata/RHSA-2026:34196
- https://access.redhat.com/errata/RHSA-2026:34197
- https://access.redhat.com/errata/RHSA-2026:34365
- https://access.redhat.com/errata/RHSA-2026:36651
- https://access.redhat.com/errata/RHSA-2026:36796
- https://access.redhat.com/errata/RHSA-2026:39810
- https://access.redhat.com/errata/RHSA-2026:40118
- https://access.redhat.com/errata/RHSA-2026:40945
- https://access.redhat.com/errata/RHSA-2026:41928
- https://access.redhat.com/errata/RHSA-2026:42043
- https://access.redhat.com/errata/RHSA-2026:42047
- https://access.redhat.com/errata/RHSA-2026:42049
- https://access.redhat.com/errata/RHSA-2026:42050
- https://access.redhat.com/errata/RHSA-2026:42051
- https://access.redhat.com/errata/RHSA-2026:47952
- https://access.redhat.com/errata/RHSA-2026:49702
- https://access.redhat.com/errata/RHSA-2026:49703
- https://access.redhat.com/errata/RHSA-2026:49712
- https://access.redhat.com/errata/RHSA-2026:51033
- https://access.redhat.com/errata/RHSA-2026:51288
- https://access.redhat.com/errata/RHSA-2026:54757
- https://access.redhat.com/errata/RHSA-2026:56143
- https://access.redhat.com/errata/RHSA-2026:56223
- https://access.redhat.com/errata/RHSA-2026:57126
Timeline
- Published
- Apr 8, 2026
- Last modified
- Sep 18, 2026
- NVD status
- Modified