CVE•Published 2026-04-30•Modified 2026-06-02•0 articles on news•6 live references•NVD data

CVE-2026-3833Gnu · Gnutls

Vulnerability data via NVD (ingested)

CVSS v3.1

6.5

MEDIUM

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

EPSS percentile

Exploit Prediction Scoring System · top 91% of all CVEs

Weaknesses (CWE)

CWE-178Improper Handling of Case Sensitivity

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.

Timeline

Published 2026-04-30

Modified 2026-06-02

External references

NVD MITRE Exploit-DB Sploitus trickest/cve VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-3833

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Gnu Gnutls"

All exposed Gnu Gnutls instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Gnutls"

HTTP body or banner mentions "Gnutls" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2026-3833