USN-8539-1: GnuTLS vulnerabilities

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 could possibly use this issue to bypass certificate validation,
leading to a machine-in-the-middle attack. (CVE-2026-42012)

Haruto Kimura and Joshua Rogers discovered that GnuTLS incorrectly fell
back to Common Name checks when subject alternative names were
oversized. A remote attacker could possibly use this issue to bypass
certificate validation, leading to a machine-in-the-middle attack.
(CVE-2026-42013)

Luigino Camastra and Joshua Rogers discovered that GnuTLS had a
use-after-free issue when changing PKCS#11 token security officer PINs
in certain cases. An attacker could possibly use this issue to cause
GnuTLS to crash, resulting in a denial of service, or execute arbitrary
code. (CVE-2026-42014)

Zou Dikai discovered that GnuTLS did not properly validate PKCS#12 bag
sizes in certain cases. An attacker could possibly use this issue to
cause GnuTLS to crash, resulting in a denial of service, or execute
arbitrary code. (CVE-2026-42015)