Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2025-54140 is a high-severity Path Traversal (CWE-22) vulnerability. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 48th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
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.
pyLoad, a free and open-source Python download manager, contains an authenticated path traversal vulnerability in version 0.5.0b3.dev89. The flaw resides in the /json/upload endpoint and stems from insufficient validation of uploaded filenames, allowing directory traversal outside the intended upload folder under CWE-22. An attacker who can reach the endpoint can therefore write files to arbitrary locations on the filesystem accessible to the pyLoad process, with a CVSS 3.1 score of 7.5 reflecting network attack vector, low complexity, and high integrity impact.
An authenticated user can exploit the issue by supplying a crafted filename containing path traversal sequences during an upload request. Successful exploitation permits writing arbitrary content to any writable location, which can be leveraged for remote code execution, local privilege escalation, system compromise, persistence mechanisms, or installation of backdoors.
The vulnerability is resolved in version 0.5.0b3.dev90. Public references, including the GitHub Security Advisory GHSA-xqpg-92fq-grfg and the associated commit, confirm the patch and provide the code-level details of the fix in the json_blueprint.py handler.
The EPSS score remains flat at 0.0156 with no material increase after disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-22382
Vulnerability Data
pyLoad is a free and open-source Download Manager written in pure Python. In version 0.5.0b3.dev89, an authenticated path traversal vulnerability exists in the /json/upload endpoint of pyLoad. By manipulating the filename of an uploaded file, an attacker can traverse out…
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of the intended upload directory, allowing them to write arbitrary files to any location on the system accessible to the pyLoad process. This may lead to: Remote Code Execution (RCE), local privilege escalation, system-wide compromise, persistence, and backdoors. This is fixed in version 0.5.0b3.dev90.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V5.3.2
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.
Least privilege reduces the impact of any unauthorized file access obtained via traversal.
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.
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.
PR.AA-05 defines and reviews access policies but does not address code-level pathname neutralization, so neither direction prevents CWE-22.
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.