CVE intelligence and bounded remediation
CVE-2025-66449 — ConvertXis a self-hosted online file converter
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.
- Severity
- High
- CVSS
- 8.8 (3.1)
- Published
- 2025-12-16
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-22, CWE-73, CWE-434
Affected products
- c4illin / convertx
Matched remediation archetype
Path traversal, unsafe upload, and file handling
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace untrusted filenames, archive entries, URLs, and path segments into read, write, include, extraction, and upload operations.
- Identify filesystem roots, mount permissions, symbolic-link behavior, archive handling, and whether uploaded content is web-accessible or executable.
- Review canonicalization and containment checks across supported operating systems and storage backends.
Remediate safely
- Generate server-side storage identifiers and resolve paths beneath a fixed root using filesystem-aware containment checks.
- Reject absolute, parent-relative, alternate-separator, device, link, and archive entries that escape the intended root.
- Store uploads outside executable or served paths, validate type and size, and use private atomic temporary files.
Authoritative sources
Complete CVE record and remediation plan
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