SB2020030917 - Arbitrary file upload in BookStack
Published: March 9, 2020 Updated: July 17, 2020
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Arbitrary file upload (CVE-ID: CVE-2020-5256)
CWE-ID: CWE-434 - Unrestricted Upload of File with Dangerous Type
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
The vulnerability allows a remote authenticated user to execute arbitrary code.
BookStack before version 0.25.5 has a vulnerability where a user could upload PHP files through image upload functions, which would allow them to execute code on the host system remotely. They would then have the permissions of the PHP process. This most impacts scenarios where non-trusted users are given permission to upload images in any area of the application. The issue was addressed in a series of patches in versions 0.25.3, 0.25.4 and 0.25.5. Users should upgrade to at least v0.25.5 to avoid this vulnerability.
Remediation
Install update from vendor's website.