NVD Vulnerability Detail
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CVE-2026-3833
Summary

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.

Publication Date May 1, 2026, 3:16 a.m.
Registration Date May 1, 2026, 4:07 a.m.
Last Update May 1, 2026, 3:16 a.m.
CVSS3.1 : MEDIUM
スコア 6.5
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
攻撃元区分(AV) ネットワーク
攻撃条件の複雑さ(AC)
攻撃に必要な特権レベル(PR) 不要
利用者の関与(UI) 不要
影響の想定範囲(S) 変更なし
機密性への影響(C)
完全性への影響(I)
可用性への影響(A) なし
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