CVE-2020-27304
CVSS v3
9.8
CRITICAL
EPSS Score
3.2 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
The CivetWeb web library does not validate uploaded filepaths when running on an OS other than Windows, when using the built-in HTTP form-based file upload mechanism, via the mg_handle_form_request API. Web applications that use the file upload form handler, and use parts of the user-controlled filename in the output path, are susceptible to directory traversal
Technical details
- Published
- 2021-10-21
Frequently asked questions
What is CVE-2020-27304?
The CivetWeb web library does not validate uploaded filepaths when running on an OS other than Windows, when using the built-in HTTP form-based file upload mechanism, via the mg_handle_form_request API. Web applications that use the file upload form handler, and use parts of the user-controlled filename in the output path, are susceptible to directory traversal
Is CVE-2020-27304 actively exploited?
Active exploitation of CVE-2020-27304 has not been confirmed. Its EPSS score was 3.2% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2020-27304?
CVE-2020-27304 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2020-27304 affecting your environment?
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