CVE-2026-0992 is a resource exhaustion vulnerability found in the libxml2 library, a widely used XML parsing library integrated into Red Hat Enterprise Linux 10. The flaw arises when the XML catalog processing component encounters repeated <nextCatalog> elements that reference the same downstream catalog multiple times. This causes the parser to redundantly traverse the same catalog chains repeatedly, leading to uncontrolled CPU consumption. The vulnerability can be triggered by a remote attacker supplying crafted XML catalogs, which when processed by an application relying on libxml2, results in excessive CPU usage and degraded availability of the affected application or service. The attack vector is local, meaning the attacker must have the ability to supply or influence XML catalog input locally on the system. The attack complexity is high, indicating that exploitation requires specific conditions or knowledge. No privileges or user interaction are required, which slightly lowers the barrier once local access is obtained. The vulnerability impacts availability only, with no confidentiality or integrity implications. There are no known public exploits or patches currently available. This vulnerability is relevant for any Red Hat Enterprise Linux 10 deployments that use libxml2 for XML catalog processing, which is common in many enterprise applications and services that handle XML data.

For European organizations running Red Hat Enterprise Linux 10, this vulnerability could lead to denial-of-service conditions in critical applications that process XML catalogs using libxml2. The excessive CPU consumption may degrade system performance or cause service outages, impacting business continuity and operational efficiency. Sectors relying heavily on XML processing, such as finance, telecommunications, and government services, could experience disruptions. Although the attack requires local access and has high complexity, insider threats or compromised internal systems could exploit this vulnerability to cause service degradation. The impact is limited to availability, with no direct data breach or integrity compromise. However, availability issues can indirectly affect compliance with regulations like GDPR if services become unavailable or data processing is interrupted.

European organizations should monitor for updates and patches from Red Hat addressing CVE-2026-0992 and apply them promptly once available. In the interim, restrict local access to systems running Red Hat Enterprise Linux 10 to trusted users only, minimizing the risk of local exploitation. Implement strict input validation and sanitization for XML catalogs processed by applications using libxml2 to detect and block crafted catalogs with repeated <nextCatalog> elements. Employ resource usage monitoring and alerting to detect abnormal CPU consumption patterns indicative of exploitation attempts. Consider isolating or sandboxing XML processing components to limit the impact of potential resource exhaustion. Additionally, review and harden internal access controls and audit logs to detect suspicious activities related to XML catalog processing. Engage with Red Hat support for any recommended workarounds or configuration changes that can mitigate the vulnerability before patches are released.