CVE-2023-2858 is a buffer over-read vulnerability categorized under CWE-787 found in the NetScaler file parser component of Wireshark versions 3.6.0 through 3.6.13 and 4.0.0 through 4.0.5. This vulnerability allows an attacker to craft a malicious capture file that, when opened by a user in the vulnerable Wireshark application, causes the program to crash, resulting in a denial of service (DoS). The flaw stems from improper bounds checking during the parsing of NetScaler files, leading to reading memory beyond the intended buffer. The CVSS 3.1 base score of 5.3 reflects a medium severity, with an attack vector of local (AV:L), low complexity (AC:L), no privileges required (PR:N), but requiring user interaction (UI:R). The impact affects confidentiality, integrity, and availability to a limited degree, mainly through application crashes that could disrupt network analysis workflows. No known exploits have been reported in the wild, and no official patches have been linked at the time of publication. This vulnerability is significant for organizations relying on Wireshark for network traffic inspection, forensic analysis, and security monitoring, as it could be leveraged to disrupt these activities by causing application instability or denial of service.

For European organizations, the primary impact of CVE-2023-2858 is operational disruption due to denial of service when using vulnerable Wireshark versions. This can affect network administrators, security analysts, and incident responders who rely on Wireshark for packet analysis and troubleshooting. In critical infrastructure sectors such as telecommunications, finance, and government, such disruptions could delay detection and response to other security incidents, indirectly increasing risk exposure. While the vulnerability does not allow remote code execution or data exfiltration, the loss of availability and potential integrity issues in analysis results can degrade security posture. Organizations that process untrusted capture files or share capture files across teams are at higher risk. The absence of known exploits reduces immediate threat but does not eliminate the risk of future exploitation. Overall, the impact is moderate but relevant for environments where Wireshark is a key tool for network security operations.

1. Upgrade Wireshark to versions later than 3.6.13 or 4.0.5 as soon as official patches are released to address CVE-2023-2858. 2. Until patches are available, avoid opening capture files from untrusted or unknown sources to minimize exposure to crafted malicious files. 3. Implement sandboxing or containerization for Wireshark instances to isolate potential crashes and prevent broader system impact. 4. Employ strict access controls and monitoring on systems used for network analysis to detect anomalous activity or repeated crashes. 5. Educate security teams about the risk of opening unverified capture files and establish procedures for verifying file integrity before analysis. 6. Consider using alternative packet analysis tools or offline analysis methods for suspicious capture files until the vulnerability is mitigated. 7. Maintain updated incident response plans that include handling denial of service scenarios affecting security tools.