Multiple GnuTLS Vulnerabilities Lead to Denial of Service Risks

A series of vulnerabilities in GnuTLS, discovered by researchers including Joshua Rogers and Oleh Konko, affect multiple Ubuntu releases. These vulnerabilities could allow remote attackers to exploit malformed DTLS handshake fragments and improperly validated OCSP responses, potentially leading to denial of service or machine-in-the-middle attacks. The affected Ubuntu versions include 26.04 LTS, 25.10, 24.04 LTS, and 22.04 LTS. Specific CVEs include CVE-2026-33845, CVE-2026-33846, CVE-2026-3832, CVE-2026-3833, and CVE-2026-42009. Users are advised to update their systems to mitigate these risks. The vulnerabilities were published between April 30 and May 18, 2026, with the advisory released on May 20, 2026.

Key Points: • GnuTLS vulnerabilities could lead to denial of service and sensitive data exposure. • Affected Ubuntu versions include 26.04 LTS and earlier releases. • Users are urged to update their systems to the latest package versions to mitigate risks.