USN-8284-1

Joshua Rogers discovered that GnuTLS did not properly handle malformed DTLS handshake fragments in certain cases. A remote attacker could possibly use this issue to obtain sensitive information, or cause a denial of service. (CVE-2026-33845)

Haruto Kimura, Oscar Reparaz, and Zou Dikai discovered that GnuTLS did not properly validate DTLS handshake fragment lengths in certain cases. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service, or execute arbitrary code. (CVE-2026-33846)

Oleh Konko and Joshua Rogers discovered that GnuTLS did not properly validate OCSP responses in certain cases. A remote attacker could possibly use this issue to bypass certificate revocation checks, leading to a machine-in-the-middle attack. (CVE-2026-3832)

Oleh Konko and Joshua Rogers discovered that GnuTLS did not properly handle case-insensitive name constraints in certain cases. A remote attacker could possibly use this issue to bypass certificate validation, leading to a machine-in-the-middle attack. (CVE-2026-3833)

Joshua Rogers discovered that GnuTLS did not properly order DTLS packets with duplicate sequence numbers in certain cases. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service. (CVE-2026-42009)

Joshua Rogers discovered that GnuTLS did not properly handle usernames containing NUL characters in certain RSA-PSK configurations. A remote attacker could possibly use this issue to bypass authentication and gain unintended access to services. (CVE-2026-42010)

Haruto Kimura discovered that GnuTLS did not properly apply permitted name constraints in certain certificate validation paths. A remote attacker could possibly use this issue to bypass certificate validation, leading to a machine-in-the-middle attack. (CVE-2026-42011)

Oleh Konko discovered that GnuTLS incorrectly fell back to Common Name checks for certain URI and SRV subject alternative names. A remote attacker...