CVE-2025-14831 is a vulnerability identified in the GnuTLS library component of Red Hat Enterprise Linux 10. The issue stems from inefficient algorithmic complexity when processing TLS certificates that contain a large number of name constraints and subject alternative names (SANs). Specifically, the certificate parsing logic does not efficiently handle these fields, leading to excessive CPU and memory consumption when processing specially crafted malicious certificates. This resource exhaustion can cause a denial of service (DoS) condition, impacting system availability. The vulnerability is remotely exploitable over the network without requiring any privileges or user interaction, as it involves the processing of certificates typically during TLS handshakes or certificate validation routines. The CVSS v3.1 base score is 5.3 (medium), reflecting the lack of impact on confidentiality or integrity but a significant impact on availability. There are no known exploits in the wild at the time of publication, and no patches have been linked yet, though Red Hat is the vendor responsible for addressing the issue. This vulnerability is particularly relevant for environments that handle numerous or complex TLS certificates, such as web servers, VPN gateways, or other network security appliances running Red Hat Enterprise Linux 10.

For European organizations, the primary impact is on the availability of systems running Red Hat Enterprise Linux 10 that utilize GnuTLS for TLS certificate processing. Services that rely on TLS for secure communications—such as web servers, mail servers, VPNs, and internal authentication systems—could be disrupted by an attacker sending malicious certificates designed to exhaust CPU and memory resources. This could lead to service outages, degraded performance, or system crashes, affecting business continuity and potentially causing operational downtime. While confidentiality and integrity are not directly impacted, the denial of service could indirectly affect security posture by disrupting security monitoring or incident response capabilities. Organizations in sectors such as finance, healthcare, government, and critical infrastructure in Europe, which often rely on Red Hat Enterprise Linux for their secure communications, are at heightened risk. The medium severity rating suggests that while the threat is significant, it is not critical, but still warrants timely mitigation to prevent potential exploitation.

1. Monitor TLS certificate processing logs and system resource usage to detect unusual spikes in CPU or memory consumption that may indicate exploitation attempts. 2. Implement rate limiting or filtering on incoming TLS connections to reduce exposure to malicious certificates with excessive name constraints or SANs. 3. Where possible, restrict or validate certificate complexity on the client or server side to prevent processing of certificates with abnormally large numbers of name constraints or SANs. 4. Apply security updates and patches from Red Hat promptly once they become available to address this vulnerability. 5. Consider deploying network-level protections such as Web Application Firewalls (WAFs) or Intrusion Prevention Systems (IPS) configured to detect and block malformed or suspicious TLS certificates. 6. Conduct regular vulnerability assessments and penetration testing focused on TLS certificate handling to identify potential weaknesses. 7. Educate system administrators and security teams about this vulnerability to ensure awareness and readiness to respond to potential incidents.