CVE-2025-13945 is a vulnerability identified in Wireshark version 4.6.0, specifically within its HTTP3 protocol dissector component. The issue arises from CWE-1325, which involves improperly controlled sequential memory allocation. This flaw can be triggered when Wireshark processes malformed or malicious HTTP3 traffic, leading to a crash of the application. The crash results in a denial of service (DoS) condition, disrupting the ability of the network analyst or monitoring system to capture and analyze network traffic effectively. The vulnerability requires local access to the system running Wireshark and user interaction to open or analyze the crafted packet capture data. There is no impact on confidentiality or integrity, as the flaw does not allow code execution or data manipulation, only service disruption. The CVSS 3.1 base score is 5.5, indicating a medium severity level, with an attack vector classified as local (AV:L), low attack complexity (AC:L), no privileges required (PR:N), and requiring user interaction (UI:R). No patches or exploits are currently publicly available, but the vulnerability is published and recognized by the Wireshark Foundation and CVE databases. This vulnerability is particularly relevant for environments where Wireshark is used extensively for network diagnostics, forensic analysis, or security monitoring, especially when handling HTTP3 traffic.

For European organizations, the primary impact of CVE-2025-13945 is the potential denial of service on systems running Wireshark 4.6.0. This can disrupt network monitoring and incident response activities, delaying detection and mitigation of other threats. Critical infrastructure operators, financial institutions, and large enterprises relying on Wireshark for real-time traffic analysis may face operational challenges. Although the vulnerability does not compromise data confidentiality or integrity, the loss of availability can hinder security teams' ability to maintain situational awareness. In sectors with stringent regulatory requirements for continuous monitoring, such as finance and healthcare, this disruption could have compliance implications. Additionally, organizations using automated tools that integrate Wireshark for packet analysis might experience workflow interruptions. The lack of known exploits reduces immediate risk, but the presence of the vulnerability necessitates proactive mitigation to avoid potential future exploitation or accidental crashes during routine operations.

To mitigate CVE-2025-13945, organizations should first verify if they are running Wireshark version 4.6.0 and plan to upgrade to a patched version once released by the Wireshark Foundation. Until a patch is available, limit exposure by restricting access to Wireshark installations to trusted personnel only and avoid opening untrusted or suspicious packet captures, especially those containing HTTP3 traffic. Implement network segmentation to isolate systems used for network analysis from general user environments to reduce the risk of malicious packet injection. Employ strict input validation and scanning of capture files before analysis to detect malformed packets. Additionally, consider using alternative or supplementary network analysis tools that do not exhibit this vulnerability. Regularly monitor Wireshark and security advisories for updates or patches addressing this issue. Finally, incorporate this vulnerability into incident response and vulnerability management workflows to ensure timely remediation.