CVE-2025-8671 is a high-severity vulnerability affecting the SUSE Linux Enterprise Module for Development Tools, specifically version 15 SP2. The vulnerability arises from an improper resource shutdown or release issue (CWE-404) related to the handling of HTTP/2 streams. According to the HTTP/2 protocol, when a stream is reset by the server, it should be considered closed at the protocol level, and all associated resources should be released. However, in this implementation, a mismatch between client-triggered server-sent stream resets and the internal architecture causes the backend processing to continue despite the protocol-level closure. An attacker can exploit this by opening multiple HTTP/2 streams and rapidly triggering resets using malformed frames or flow control errors. This leads to incorrect stream accounting, allowing the server to handle an unbounded number of concurrent streams on a single connection. The consequence is excessive consumption of server resources, which can culminate in a denial-of-service (DoS) condition. The vulnerability does not impact confidentiality or integrity but severely affects availability. The CVSS v3.1 score is 7.5 (high), reflecting the network attack vector, no required privileges or user interaction, and the high impact on availability. No known exploits are currently in the wild, and no patches have been linked yet, indicating that mitigation may rely on configuration or monitoring until a fix is released.

For European organizations, this vulnerability poses a significant risk to the availability of services running on SUSE Linux Enterprise Module for Development Tools 15 SP2, especially those utilizing HTTP/2 connections. Organizations relying on this module for development or production environments may face service disruptions due to resource exhaustion caused by malicious clients exploiting this flaw. This can affect web servers, APIs, and internal tools that communicate over HTTP/2, leading to downtime, degraded performance, and potential loss of business continuity. Critical infrastructure providers, financial institutions, and enterprises with high availability requirements are particularly vulnerable. Additionally, the lack of authentication or user interaction required for exploitation means that attackers can remotely trigger the DoS, increasing the attack surface. The impact is compounded in environments with high traffic or exposed HTTP/2 endpoints, potentially allowing attackers to cause widespread disruption.

1. Monitor HTTP/2 traffic for abnormal patterns such as rapid stream resets or malformed frames that could indicate exploitation attempts. 2. Implement rate limiting on HTTP/2 connections to restrict the number of concurrent streams and resets per client to prevent resource exhaustion. 3. Temporarily disable or restrict HTTP/2 support on affected SUSE Linux Enterprise Module for Development Tools 15 SP2 instances if feasible, until patches are available. 4. Employ network-level protections such as Web Application Firewalls (WAFs) or Intrusion Prevention Systems (IPS) configured to detect and block malformed HTTP/2 frames or suspicious reset patterns. 5. Stay updated with SUSE security advisories and apply patches promptly once released. 6. Conduct regular resource usage audits and configure alerting for unusual spikes in server resource consumption related to HTTP/2 services. 7. Consider isolating critical services using containerization or virtualization to limit the blast radius of potential DoS attacks exploiting this vulnerability.