EIP-2020-0032

The Serv-U File Server supports site specific commands which may not be universally supported by all FTP clients. Among these is the SITE EXEC command which allows a user to execute programs and scripts remotely, if the execute permission is present on the folder where a given program / script resides. A command injection vulnerability exists in this functionality due to improper sanitization of user-supplied parameters provided to the ShellExecuteExW routine. Successful exploitation results in arbitrary command execution under the context of the file server.

Vulnerability Identifiers

• Exodus Intelligence: EIP-2019-0032
• MITRE CVE: CVE-2021-35223

Vulnerability Metrics

• CVSSv2 Score: 9.4

Vendor References

• https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_15-2-4_release_notes.htm
  

Discovery Credit

• Exodus Intelligence

Disclosure Timeline

• Disclosed to affected vendor: May 14th, 2021
• Disclosed to public: September 24th, 2021

Further Information

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