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
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
| Link | Tags |
|---|---|
| https://jfrog.com/blog/cve-2020-27304-rce-via-directory-traversal-in-civetweb-http-server/ | third party advisory exploit |
| https://groups.google.com/g/civetweb/c/yPBxNXdGgJQ | third party advisory mailing list |
| https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf | third party advisory patch |
| https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf |