CVE-2026-3833

Low

No strong exploitation signal.

CVSS base

6.5 MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS — probability of exploitation (30 days)

0.6%

45.7th percentile

CISA KEV

Not listed

Weakness / dates

CWE-178

Published 2026-04-30 · modified 2026-09-17

CVSS breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	N	None
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	L	Low
Integrity	L	Low
Availability	N	None

Timeline

2026-04-30 — Published (NVD)
2026-09-17 — Last modified (NVD)

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.

Affected

gnu redhat

References

Official: NVD · CVE.org