Vulnerability CVE-2026-3833: Information
Description
A flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of `nameConstraints` labels, specifically for `dNSName` (DNS) or `rfc822Name` (email) constraints within `excludedSubtrees` or `permittedSubtrees`. A remote attacker can exploit this by crafting a leaf certificate with casing differences in the Subject Alternative Name (SAN), leading to a policy bypass where a certificate that should be rejected is instead accepted. This could result in unauthorized access or information disclosure.
Severity: HIGH (7.4)
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Fixed packages
Package name | Branch | Fixed in version | Version from repository | Errata ID | Task # | State |
|---|---|---|---|---|---|---|
| gnutls30 | sisyphus | 3.8.13-alt1 | 3.8.13-alt1 | ALT-PU-2026-7123-1 | 417120 | Fixed |
| gnutls30 | sisyphus_e2k | 3.8.13-alt1 | 3.8.13-alt1 | ALT-PU-2026-7620-1 | - | Fixed |
| gnutls30 | sisyphus_riscv64 | 3.8.13-alt1 | 3.8.13-alt1 | ALT-PU-2026-7535-1 | - | Fixed |
| gnutls30 | sisyphus_loongarch64 | 3.8.13-alt1 | 3.8.13-alt1 | ALT-PU-2026-7498-1 | - | Fixed |
| gnutls30 | p11 | 3.8.13-alt1 | 3.8.13-alt1 | ALT-PU-2026-7127-2 | 417121 | Fixed |
| gnutls30 | p10 | 3.6.16-alt11 | 3.6.16-alt11 | ALT-PU-2026-7344-2 | 417556 | Fixed |
| gnutls30 | p10_e2k | 3.6.16-alt11 | 3.6.16-alt11 | ALT-PU-2026-7867-1 | - | Fixed |
| gnutls30 | c10f2 | 3.6.16-alt11 | 3.6.16-alt11 | ALT-PU-2026-7348-2 | 417557 | Fixed |
References to Advisories, Solutions, and Tools
Hyperlink | Resource |
|---|---|
| https://access.redhat.com/errata/RHSA-2026:13274 |
|
| https://access.redhat.com/security/cve/CVE-2026-3833 |
|
| https://bugzilla.redhat.com/show_bug.cgi?id=2445763 |
|
| https://gitlab.com/gnutls/gnutls/-/issues/1803 |
|