SB2023020750 - Dangerous file upload in Zulip Server

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Main Vulnerability Database SB2023020750

SB2023020750 - Dangerous file upload in Zulip Server

Published: February 7, 2023

Security Bulletin ID SB2023020750
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Arbitrary file upload (CVE-ID: CVE-2023-22735)

CWE-ID: CWE-434 - Unrestricted Upload of File with Dangerous Type

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:U/U:Green


The vulnerability allows a remote user to perform XSS attacks.

The vulnerability exists due to application allows to upload files with arbitrary Content-Type. Such file will be served from the Zulip hostname with Content-Disposition: inline and no Content-Security-Policy header. A remote user can upload a malicious file and execute arbitrary Javascript in the victim's browser in security context of the website.


Remediation

Install update from vendor's website.

References