CVE-2025-13502 is a vulnerability identified in WebKitGTK and WPE WebKit, components widely used in Linux-based browsers and embedded systems for rendering web content. The flaw arises from an integer overflow or wraparound condition that leads to an out-of-bounds read and an integer underflow within the GLib remote inspector server component. This vulnerability can be triggered remotely by sending a specially crafted payload, causing the UIProcess to crash. The UIProcess crash results in a denial-of-service (DoS) condition, disrupting the availability of applications relying on WebKitGTK for web content rendering. The vulnerability has a CVSS 3.1 base score of 7.5, reflecting its high severity due to network attack vector, no required privileges or user interaction, and a significant impact on availability. Although the vulnerability does not compromise confidentiality or integrity, the DoS impact can affect user experience and service continuity. No public exploits have been reported yet, but the vulnerability's characteristics make it a candidate for exploitation in the future. The affected versions are not explicitly detailed beyond '0', indicating potentially all current versions at the time of disclosure are vulnerable. The flaw specifically targets the GLib remote inspector server, a component used for debugging and inspecting web content, which may be exposed in development or production environments depending on configuration. The vulnerability was published on November 25, 2025, with the Red Hat security team as the assigner. Mitigation currently relies on patching once updates are released and limiting network exposure of the GLib remote inspector server to trusted environments only.

For European organizations, the primary impact of CVE-2025-13502 is the potential for denial-of-service attacks against applications using WebKitGTK or WPE WebKit, which are common in Linux-based environments and embedded systems. This can lead to service interruptions, degraded user experience, and operational downtime, particularly for organizations relying on web applications or devices that embed these components. Sectors such as telecommunications, finance, and public services that utilize Linux-based browsers or custom embedded web interfaces may experience disruptions. The lack of confidentiality or integrity impact reduces the risk of data breaches, but availability loss can still have significant operational and reputational consequences. Organizations with remote debugging or inspection enabled via the GLib remote inspector server are at higher risk if this service is exposed to untrusted networks. The absence of known exploits in the wild currently lowers immediate risk but does not eliminate the threat, especially given the vulnerability's high CVSS score and ease of exploitation without authentication or user interaction.

1. Monitor vendor advisories and apply security patches for WebKitGTK and WPE WebKit promptly once available. 2. Restrict network access to the GLib remote inspector server by implementing firewall rules or network segmentation to limit exposure to trusted hosts only. 3. Disable or restrict remote inspection and debugging features in production environments unless absolutely necessary. 4. Employ application-layer protections such as web application firewalls (WAFs) to detect and block anomalous payloads targeting the GLib remote inspector server. 5. Conduct regular security assessments and penetration tests focusing on WebKitGTK-based applications to identify potential exposure. 6. Maintain up-to-date intrusion detection systems (IDS) and monitoring to detect unusual crashes or DoS attempts related to this vulnerability. 7. Educate development and operations teams about the risks associated with enabling remote inspection features and enforce secure configuration baselines.