CVE-2025-32990 is a heap-based buffer overflow vulnerability identified in the GnuTLS software, specifically within the certtool utility's template parsing logic. The flaw is an off-by-one error that occurs when certtool reads certain settings from a template file. This results in an out-of-bounds NULL pointer write, causing memory corruption. The corrupted memory state can lead to a denial-of-service (DoS) condition by crashing the affected system or process. The vulnerability does not require any authentication or user interaction to be exploited, and it can be triggered remotely over the network since the attack vector is network accessible (AV:N). The vulnerability affects Red Hat Enterprise Linux 10, which bundles GnuTLS as a core component for cryptographic operations. The CVSS v3.1 base score is 6.5, indicating a medium severity level, with no impact on confidentiality but partial impact on integrity and availability. No known exploits are currently reported in the wild, and no patches have been linked yet. The flaw arises from improper bounds checking during template parsing, a critical operation in certificate generation and management, which could disrupt cryptographic services relying on GnuTLS.

For European organizations, this vulnerability poses a risk primarily to systems running Red Hat Enterprise Linux 10, especially those utilizing certtool for certificate management or automated certificate generation. The denial-of-service impact could disrupt critical infrastructure services, including secure communications, VPNs, and internal PKI operations. Organizations in sectors such as finance, healthcare, government, and telecommunications, which rely heavily on cryptographic services for data protection and regulatory compliance, could face operational downtime and service interruptions. Although the vulnerability does not directly expose confidential data, the integrity and availability of cryptographic functions are compromised, potentially undermining trust in secure communications. The lack of authentication and user interaction requirements increases the risk of automated exploitation attempts, which could be leveraged in targeted attacks or widespread scanning campaigns. Given the widespread use of Red Hat Enterprise Linux in European enterprises and public sector environments, the impact could be significant if not mitigated promptly.

Organizations should prioritize updating GnuTLS and certtool components as soon as patches become available from Red Hat or upstream sources. In the interim, restricting access to systems running certtool, especially limiting network exposure of certificate management services, can reduce exploitation risk. Implementing strict input validation and sanitization on template files used by certtool can help prevent malformed inputs triggering the vulnerability. Monitoring system logs for unusual crashes or memory corruption events related to certtool may provide early detection of exploitation attempts. Employing application whitelisting and process isolation techniques can limit the blast radius of a successful DoS attack. Additionally, organizations should review and harden their cryptographic infrastructure to ensure redundancy and failover capabilities to maintain availability during potential service disruptions.