CVE-2026-7376: Sharkd Denial of Service Vulnerability

CVE-2026-7376 Overview

CVE-2026-7376 is a Null Pointer Dereference vulnerability in Wireshark's sharkd component that allows for denial of service attacks. The vulnerability affects sharkd versions 4.6.0 through 4.6.4 and 4.4.0 through 4.4.14. When exploited, this flaw causes the sharkd process to crash, disrupting network traffic analysis operations.

Critical Impact
Exploitation of this vulnerability leads to a denial of service condition, impacting network monitoring and forensic analysis capabilities that depend on sharkd.

Affected Products

Wireshark sharkd 4.6.0 to 4.6.4
Wireshark sharkd 4.4.0 to 4.4.14

Discovery Timeline

2026-04-30 - CVE-2026-7376 published to NVD
2026-04-30 - Last updated in NVD database

Technical Details for CVE-2026-7376

Vulnerability Analysis

This vulnerability is classified as CWE-476 (NULL Pointer Dereference). The flaw exists within the sharkd component of Wireshark, which serves as a network packet dissection daemon providing a JSON-based API. Under specific conditions, sharkd fails to properly validate pointer references before dereferencing them, leading to an application crash.

The local attack vector requires user interaction, meaning an attacker must craft a malicious input file or network capture that, when processed by sharkd, triggers the null pointer dereference. While this vulnerability does not allow for code execution or data compromise, the availability impact is significant as it completely disrupts the sharkd service.

Root Cause

The root cause stems from insufficient null pointer validation within sharkd's processing logic. When handling certain packet data or API requests, the code path fails to check whether a pointer is valid before attempting to dereference it. This results in an unhandled exception that terminates the sharkd process.

Attack Vector

This vulnerability requires local access and user interaction to exploit. An attacker would need to provide a specially crafted capture file or input that, when processed by sharkd, triggers the vulnerable code path. The attack scenario typically involves:

Creating a malicious packet capture file designed to trigger the null pointer condition
Convincing a user to open or process the file with sharkd
The sharkd process crashes upon processing the malicious input

For technical details about the specific trigger conditions, refer to the Wireshark Security Advisory WNPA-SEC-2026-48 and the GitLab Work Item #21206.

Detection Methods for CVE-2026-7376

Indicators of Compromise

Unexpected sharkd process terminations or crash logs
Core dump files generated by sharkd with null pointer dereference signatures
Increased frequency of sharkd service restarts
Presence of unusual or malformed capture files in processing directories

Detection Strategies

Monitor sharkd process stability and implement alerting on unexpected terminations
Review system logs for segmentation fault errors associated with sharkd
Implement file integrity monitoring on directories where capture files are processed
Use application-level monitoring to track sharkd API response failures

Monitoring Recommendations

Configure process monitoring tools to alert on sharkd crashes
Implement logging aggregation for crash dumps and core files related to Wireshark components
Set up automated health checks for sharkd service availability
Monitor for patterns of repeated service failures that may indicate exploitation attempts

How to Mitigate CVE-2026-7376

Immediate Actions Required

Update Wireshark to the latest patched version beyond 4.6.4 or 4.4.14
Restrict access to sharkd to trusted users only
Implement input validation on capture files before processing with sharkd
Configure process supervision to automatically restart sharkd if it crashes

Patch Information

Wireshark has addressed this vulnerability in versions newer than 4.6.4 (for the 4.6.x branch) and 4.4.14 (for the 4.4.x branch). Users should upgrade to the latest available version. Consult the Wireshark Security Advisory WNPA-SEC-2026-48 for specific patch details and updated version information.

Workarounds

Limit sharkd usage to trusted capture files from known sources only
Run sharkd in a sandboxed or containerized environment to limit crash impact
Implement process supervision with automatic restart capabilities
Consider disabling sharkd if not required for your network analysis workflow

bash

# Example: Running sharkd with process supervision using systemd
# Create a systemd service file with automatic restart
[Unit]
Description=Wireshark sharkd daemon
After=network.target

[Service]
Type=simple
ExecStart=/usr/bin/sharkd -a tcp:127.0.0.1:4446
Restart=on-failure
RestartSec=5s
User=wireshark

[Install]
WantedBy=multi-user.target