CVE-2025-32990 is a heap-based buffer overflow vulnerability identified in the GnuTLS library, specifically within the certtool utility's template parsing logic. The flaw arises from an off-by-one error when certtool reads certain settings from a template file, which leads to an out-of-bounds NULL pointer write. This memory corruption can cause the application to crash, resulting in a denial-of-service (DoS) condition. The vulnerability affects Red Hat Enterprise Linux 10, a widely used enterprise-grade Linux distribution. Exploitation requires no privileges or user interaction, as the flaw can be triggered remotely by supplying a crafted template file to certtool. The CVSS v3.1 base score is 6.5, reflecting medium severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. The impact primarily affects system integrity and availability, as the memory corruption can disrupt normal operations. No known exploits are currently reported in the wild, but the vulnerability poses a risk to systems that utilize certtool for certificate management and template parsing. The absence of a patch link suggests that a fix may still be pending or in development. Organizations relying on Red Hat Enterprise Linux 10 should monitor vendor advisories closely and prepare to deploy patches promptly to mitigate potential exploitation risks.

For European organizations, this vulnerability could lead to denial-of-service conditions on critical systems running Red Hat Enterprise Linux 10, especially those using GnuTLS certtool for certificate management. The DoS could disrupt services dependent on secure communications, such as web servers, VPN gateways, and internal PKI infrastructure. While confidentiality is not directly impacted, the integrity and availability of certificate-related processes could be compromised, potentially delaying certificate issuance or renewal workflows. This disruption may affect sectors with stringent security and uptime requirements, including finance, healthcare, government, and telecommunications. The medium severity rating indicates a moderate risk, but the ease of exploitation without authentication raises concerns for exposed systems. European organizations with automated certificate management pipelines or those that parse untrusted template files are particularly vulnerable. The lack of known exploits reduces immediate risk but does not eliminate the threat, especially as exploit code could emerge. Operational disruptions from DoS attacks could lead to compliance issues under regulations like GDPR if services are unavailable or security processes are impaired.

Organizations should immediately audit their use of the certtool utility within GnuTLS on Red Hat Enterprise Linux 10 systems. Until a patch is released, restrict access to certtool and limit the processing of untrusted or external template files to trusted administrators only. Implement strict input validation and sandboxing where possible to contain potential memory corruption effects. Monitor system logs and application behavior for crashes or anomalies related to certtool usage. Employ network segmentation and firewall rules to limit exposure of systems running certtool to untrusted networks. Prepare to deploy vendor patches promptly once available, and test updates in staging environments to ensure stability. Additionally, consider alternative certificate management tools temporarily if certtool usage is critical and cannot be sufficiently secured. Regularly review and update incident response plans to address potential DoS scenarios stemming from this vulnerability. Finally, maintain up-to-date backups and system snapshots to facilitate rapid recovery from crashes or service interruptions.