CVE-2023-2857 in Wireshark
Summary
by MITRE • 05/27/2023
BLF file parser crash in Wireshark 4.0.0 to 4.0.5 and 3.6.0 to 3.6.13 allows denial of service via crafted capture file
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 05/07/2026
The vulnerability identified as CVE-2023-2857 represents a critical denial of service flaw within Wireshark's BLF file parser component. This issue affects multiple versions of the popular network protocol analyzer, specifically targeting releases from 4.0.0 through 4.0.5 and 3.6.0 through 3.6.13. The vulnerability manifests when Wireshark attempts to process a specially crafted BLF capture file, which can cause the application to crash and terminate unexpectedly. BLF files are binary log format files used by Wireshark to store network traffic captures, making this vulnerability particularly concerning for network security professionals who rely on the tool for traffic analysis and incident response activities.
The technical root cause of this vulnerability stems from inadequate input validation within Wireshark's BLF file parsing logic. When processing malformed or maliciously crafted BLF files, the parser fails to properly handle certain data structures or offsets within the file format, leading to memory corruption or unexpected behavior that ultimately results in application crash. This type of vulnerability falls under the CWE-121 category of "Stack-based Buffer Overflow" or more specifically relates to improper input validation and error handling. The flaw demonstrates a classic example of how insufficient sanitization of user-provided input data can lead to application instability and denial of service conditions. The vulnerability is particularly dangerous because it can be triggered simply by opening a malicious BLF file, without requiring any special privileges or complex attack vectors.
The operational impact of CVE-2023-2857 extends beyond simple application crashes, potentially disrupting critical network monitoring and forensic analysis workflows. Network security teams who depend on Wireshark for traffic inspection and incident investigation may find their analysis tools become unavailable when encountering maliciously crafted capture files. This disruption can occur during security investigations, network troubleshooting sessions, or automated monitoring processes where Wireshark is used to analyze captured traffic. The vulnerability creates a scenario where an attacker could remotely or locally cause a denial of service against systems running affected Wireshark versions, effectively preventing legitimate users from performing network analysis tasks. From an attacker's perspective, this vulnerability aligns with ATT&CK technique T1498.001, "Network Denial of Service" and can be leveraged as part of broader attack chains to disrupt network security operations.
Mitigation strategies for CVE-2023-2857 primarily focus on immediate version updates to patched releases of Wireshark. Users should upgrade to Wireshark versions that have addressed this vulnerability, typically those released after the patch was developed and tested. Organizations should implement strict file validation procedures before opening BLF files in Wireshark, particularly when dealing with files received from untrusted sources or during security incident response activities. Network security teams should consider implementing sandboxing or isolated environments when analyzing potentially malicious capture files, preventing direct execution of suspect BLF files within primary analysis workstations. Additionally, administrators should monitor for any signs of exploitation attempts and maintain comprehensive logging of Wireshark usage to detect potential abuse of this vulnerability. The vulnerability serves as a reminder of the importance of input validation and proper error handling in security tools, as well as the critical need for regular security updates and patch management processes within network security infrastructure.