Gnutls

CVE-2026-42015 is a memory corruption vulnerability due to an off-by-one error in PKCS#12 bag handling in GnuTLS.

A vulnerability in gnutls (CVE-2026-42013) allows a remote attacker to bypass certificate validation by providing an oversized Subject Alternative Name (SAN), causing the validation process to fall back to the Common Name (CN) field, potentially leading to spoofing or man-in-the-middle attacks.

CVE-2026-42012 describes a vulnerability in GnuTLS where a remote attacker can spoof legitimate services or intercept sensitive information by presenting a specially crafted certificate with URI or SRV SANs, causing the certificate validation process to incorrectly fall back to checking DNS hostnames against the Common Name (CN).

A remote attacker could exploit a flaw in GnuTLS's DTLS packet reordering logic (CVE-2026-42009) to cause unstable packet ordering or undefined behavior, resulting in a denial of service.

CVE-2026-45185, a user-after-free vulnerability in Exim versions 4.97 through 4.99.2, allows an unauthenticated remote attacker to execute arbitrary code by sending crafted SMTP traffic with BDAT chunking during TLS shutdown.

A flaw in GnuTLS DTLS handshake parsing allows malformed fragments with zero length and non-zero offset, leading to an integer underflow during reassembly and resulting in an out-of-bounds read, potentially causing information disclosure or denial of service.

A remote, unauthenticated attacker can exploit CVE-2026-1584 in gnutls by sending a specially crafted ClientHello message with an invalid Pre-Shared Key (PSK) binder value during the TLS handshake, leading to a NULL pointer dereference and a denial-of-service condition.

A vulnerability in GNUTLS (CVE-2026-42010) allows a remote attacker to bypass authentication on servers configured with RSA-PSK by sending a specially crafted username containing a NUL character, leading to unauthorized access.

A heap buffer overflow vulnerability, CVE-2026-33846, exists in the DTLS handshake fragment reassembly logic of GnuTLS, allowing unauthenticated remote attackers to cause application crashes or potential memory corruption by sending crafted DTLS fragments with conflicting message lengths.