Improper access control in Zulip Server - CVE-2021-30478
Published: April 19, 2021
Vulnerability identifier: #VU52317
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-30478
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to improper access restrictions in the implementation of the "can_forge_sender" permission. A remote authenticated attacker can send messages appearing as if sent by a system bot, including to other organizations hosted by the same Zulip installation.
Affected software
Zulip Server
How to mitigate CVE-2021-30478
Install updates from vendor's website.
Zulip Server - update to 3.4