PT-2023-18677 · Zulip · Zulip

Alexmv

·

Published

2023-02-07

·

Updated

2023-02-16

·

CVE-2023-22735

CVSS v3.1

4.4

Medium

VectorAV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N
Name of the Vulnerable Software and Affected Versions Zulip versions prior to commit 2f6c5a8 but after commit 04cf68b
Description Zulip is an open-source team collaboration tool. In affected versions, users could upload files with arbitrary Content-Type which would be served from the Zulip hostname with Content-Disposition: inline and no Content-Security-Policy header, allowing them to trick other users into executing arbitrary Javascript in the context of the Zulip application. This enables session theft. Only deployments which use the S3 storage are affected, and only deployments which deployed commit 04cf68b45ebb5c03247a0d6453e35ffc175d55da, which has only been in main, not any numbered release.
Recommendations To resolve the issue, users should upgrade from main again to deploy the fix. As a temporary workaround, switching from S3 storage to the local-disk storage would nominally mitigate this, but is likely more involved than upgrading to the latest main which addresses the issue.

Exploit

Fix

Weakness Enumeration

CWE-436

Related Identifiers

CVE-2023-22735
GHSA-WM83-3764-5WQH

Affected Products

Zulip