CVE-2020-21005
Published: 03 June 2021
Summary
CVE-2020-21005 is a medium-severity Unrestricted Upload of File with Dangerous Type (CWE-434) vulnerability in Wellcms Wellcms. Its CVSS base score is 6.5 (Medium).
Operationally, ranked at the 43.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2020-13784
Vulnerability details
WellCMS 2.0 beta3 is vulnerable to File Upload. A user can log in to the CMS background and upload a picture. Because the upload file type is controllable, the user can modify the upload file type to get webshell.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Requiring identifiable owners for portable devices reduces the attack surface for unrestricted uploads of dangerous file types via anonymous media.
Dangerous file uploads can be detonated in the chamber to determine malice before any production write or execution occurs.
Prevents unrestricted writing of arbitrary or malicious firmware by keeping hardware write-protect enabled except under tightly controlled manual procedures.
Scans files from external sources on download/open/execute, blocking unrestricted uploads of dangerous file types.