CVE-2026-7379: Sharkd Memory Leak DoS Vulnerability

CVE-2026-7379 Overview

A memory leak vulnerability has been identified in the sharkd component of Wireshark, a widely-used network protocol analyzer. The vulnerability affects sharkd versions 4.6.0 to 4.6.4 and 4.4.0 to 4.4.14, allowing attackers to cause denial of service conditions through resource exhaustion. The sharkd daemon provides a JSON-based service interface for Wireshark functionality, making this vulnerability particularly concerning for environments that rely on automated packet analysis workflows.

Critical Impact
Attackers can exploit this memory leak to exhaust system resources, causing denial of service to network analysis operations and potentially impacting dependent security monitoring infrastructure.

Affected Products

Wireshark sharkd 4.6.0 through 4.6.4
Wireshark sharkd 4.4.0 through 4.4.14

Discovery Timeline

2026-04-30 - CVE CVE-2026-7379 published to NVD
2026-04-30 - Last updated in NVD database

Technical Details for CVE-2026-7379

Vulnerability Analysis

This vulnerability is classified as CWE-401 (Missing Release of Memory after Effective Lifetime), a common memory management flaw where allocated memory is not properly freed after use. In the context of sharkd, this memory leak occurs during the processing of certain operations, causing memory consumption to grow over time without being reclaimed.

The local attack vector requires user interaction, suggesting that the vulnerability is triggered when sharkd processes specifically crafted input files or malicious packet captures. As sharkd processes requests, memory allocations accumulate without proper deallocation, eventually leading to resource exhaustion. The availability impact is high, meaning successful exploitation can completely disrupt the sharkd service and potentially affect overall system stability.

Root Cause

The root cause is improper memory management within the sharkd component where allocated memory buffers are not released after their effective lifetime has ended. This is a classic CWE-401 vulnerability pattern where memory allocations occur during packet or session processing, but the corresponding free operations are missing or unreachable under certain code paths.

Attack Vector

The vulnerability requires local access to the system and user interaction to trigger. An attacker could craft a malicious packet capture file (PCAP/PCAPNG) that, when processed by sharkd, triggers the memory leak condition. Repeated processing of such files or sustained interaction with the vulnerable code path would progressively exhaust available system memory.

The attack scenario involves:

An attacker creates or obtains a specially crafted capture file
The file is processed through sharkd (either directly or via applications using the sharkd interface)
Each processing cycle leaks memory that is never reclaimed
Continued exploitation leads to memory exhaustion and denial of service

For detailed technical information, refer to the GitLab Work Item #21214 and the Wireshark Security Advisory WNPA-SEC-2026-47.

Detection Methods for CVE-2026-7379

Indicators of Compromise

Abnormal memory growth in sharkd processes over time without corresponding workload increases
System memory pressure or out-of-memory (OOM) events coinciding with sharkd activity
Unexplained sharkd process crashes or restarts due to resource exhaustion
Presence of unusual or malformed PCAP files in analysis directories

Detection Strategies

Monitor sharkd process memory usage for sustained growth patterns using tools like top, htop, or process monitoring agents
Implement memory threshold alerts for sharkd processes in your monitoring infrastructure
Enable audit logging for file access to track PCAP files being processed by sharkd
Deploy file integrity monitoring on directories where capture files are stored or processed

Monitoring Recommendations

Configure memory usage alerts with thresholds appropriate for your environment's typical sharkd workload
Establish baseline memory consumption patterns for sharkd under normal operations
Implement automatic process restart mechanisms with alerting when memory thresholds are exceeded
Review sharkd logs and system logs for OOM killer activity or memory-related errors

How to Mitigate CVE-2026-7379

Immediate Actions Required

Upgrade Wireshark to versions 4.6.5 or later (for 4.6.x branch) or 4.4.15 or later (for 4.4.x branch)
Restrict access to sharkd services to trusted users and systems only
Implement resource limits (memory cgroups or ulimits) on sharkd processes to contain potential impact
Review and validate sources of packet capture files before processing

Patch Information

Wireshark has addressed this vulnerability in updated releases. Organizations should consult the official Wireshark Security Advisory WNPA-SEC-2026-47 for specific patch information and download the latest stable release from the official Wireshark website. The GitLab Work Item #21214 contains additional technical details about the fix.

Workarounds

Implement memory limits on sharkd processes using cgroups or container resource constraints
Deploy automated process monitoring that restarts sharkd when memory usage exceeds defined thresholds
Isolate sharkd services in containers or virtual machines to limit impact on other systems
Disable or restrict sharkd access until patching can be completed in environments where it is not critical

bash

# Example: Limit sharkd memory using systemd resource controls
# Create override file for sharkd service
sudo systemctl edit sharkd

# Add the following content:
# [Service]
# MemoryMax=2G
# MemoryHigh=1536M

# Alternatively, use ulimit for manual process limits:
ulimit -v 2097152  # Limit virtual memory to 2GB
sharkd -a tcp:127.0.0.1:4446