Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2025-66449 is a high-severity Path Traversal (CWE-22) vulnerability in C4Illin Convertx. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 50th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-66449 is a vulnerability in ConvertX, a self-hosted online file converter, affecting versions prior to 0.16.0. The issue lies in the `/upload` endpoint, where the upload function directly uses the user-supplied `file.name` without sanitization. This allows arbitrary file writes on the system, including overwriting binaries, which can lead to code execution.
An authenticated user can exploit this vulnerability remotely over the network with low attack complexity and no user interaction required. Exploitation enables the attacker to overwrite system binaries with malicious files provided in the upload, achieving full code execution on the server.
The GitHub security advisory GHSA-cpww-gwgc-p72r documents the vulnerability, and version 0.16.0 includes a patch that addresses the lack of file name sanitization. The fixing commit is at https://github.com/C4illin/ConvertX/commit/550f472451755d095cf5802bc91f403e85b7129e, while the vulnerable code appears in src/pages/upload.tsx lines 27-30 at https://github.com/C4illin/ConvertX/blob/4ae2aab66ace7cdcc14c5a16ecaaf2372b9ccbdf/src/pages/upload.tsx#L27-L30.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-203483
Vulnerability Data
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…
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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.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V5.3.2V5.1.1
Mitigating Controls (NIST 800-53 r5) AI
Enforces the intended directory access authorizations that path traversal would otherwise bypass.
Input validation directly neutralizes special path elements before pathname construction occurs.
Malicious-code protection at entry points blocks dangerous file types from being accepted and executed.
Least privilege reduces the impact of any unauthorized file access obtained via traversal.
Least functionality restricts the file types and automatic processing capabilities the system will accept.
Mobile-code controls define, authorize, and block unacceptable uploaded code before automatic processing occurs.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices include input validation and path sanitization that eliminate this weakness.
Least-privilege file authorization directly limits damage from externally controlled paths.
Restricting execution of unauthorized software directly blocks dangerous uploaded files from running.
Hardened configuration baselines can enforce allowed file types and processing rules.
Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development catches path traversal via static/dynamic analysis.
Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.
Application security requirements include rules for safe file handling and canonicalization.
Secure architecture principles require least-privilege file access and directory isolation.
Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.
Information access restriction limits which files an application may read or write.