SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2022-21706

Zulip Server version 2.0.0 and above are vulnerable to insufficient access control with multi-use invitations.

CRITICAL 9.8EPSS 1.21%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.21%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Zulip is an open-source team collaboration tool with topic-based threading. Zulip Server version 2.0.0 and above are vulnerable to insufficient access control with multi-use invitations. A Zulip Server deployment which hosts multiple organizations is vulnerable to an attack where an invitation created in one organization (potentially as a role with elevated permissions) can be used to join any other organization. This bypasses any restrictions on required domains on users' email addresses, may be used to gain access to organizations which are only accessible by invitation, and may be used to gain access with elevated privileges. This issue has been patched in release 4.10. There are no known workarounds for this issue. ### Patches _Has the problem been patched? What versions should users upgrade to?_ ### Workarounds _Is there a way for users to fix or remediate the vulnerability without upgrading?_ ### References _Are there any links users can visit to find out more?_ ### For more information If you have any questions or comments about this advisory, you can discuss them on the [developer community Zulip server](https://zulip.com/developer-community/), or email the [Zulip security team](mailto:security@zulip.com).

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.21% probability · 67th percentile
CISA KEV
Not listed
Weakness
CWE-284, CWE-863
Affected
zulip/zulip server
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.