Certificate Validation

CVE-2026-42790 is a vulnerability in Microsoft products related to name constraints DNS bypass via subject CommonName fallback in public_key hostname verification.

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.

The epa4all-client library before version 1.2.2 is vulnerable to a TLS certificate validation issue, allowing a man-in-the-middle attacker to intercept SOAP traffic and sensitive patient data by presenting a malicious TLS certificate.

CVE-2026-0249 describes multiple improper certificate validation vulnerabilities in the Palo Alto Networks GlobalProtect app that could allow an attacker to intercept encrypted communications and potentially compromise the endpoint, especially on macOS, Android, and ChromeOS.

CVE-2026-0244 is an improper certificate validation vulnerability in Palo Alto Networks Prisma SD-WAN ION that allows a man-in-the-middle (MitM) attacker to impersonate the controller.

CVE-2026-0248 is an improper certificate validation vulnerability in Prisma Access Agent for Android and Chrome OS, enabling a man-in-the-middle (MitM) attack to intercept VPN traffic and capture sensitive device information by presenting a certificate issued by a trusted Certificate Authority.

ABB B&R Automation Studio versions before 6.5 are vulnerable to improper certificate validation (CVE-2025-11043), potentially allowing an unauthenticated attacker to intercept and interfere with data exchanges, necessitating patching and secure network configurations.

CVE-2026-34073 is a vulnerability in unspecified Microsoft products due to incomplete DNS name constraint enforcement on peer names, potentially leading to certificate validation bypass.

A critical improper certificate validation vulnerability in CISCO Webex versions 39.6 - 45.4 (CVE-2026-20184) allows a remote, unprivileged attacker to impersonate users, gain unauthorized access, and join meetings without authorization, potentially impacting confidentiality, integrity, and availability.