CVE-2023-28623

Unauthorized user can register an account in specific configurations in Zulip

Description

Zulip is an open-source team collaboration tool with unique topic-based threading. In the event that 1: `ZulipLDAPAuthBackend` and an external authentication backend (any aside of `ZulipLDAPAuthBackend` and `EmailAuthBackend`) are the only ones enabled in `AUTHENTICATION_BACKENDS` in `/etc/zulip/settings.py` and 2: The organization permissions don't require invitations to join. An attacker can create a new account in the organization with an arbitrary email address in their control that's not in the organization's LDAP directory. The impact is limited to installations which have this specific combination of authentication backends as described above in addition to having `Invitations are required for joining this organization` organization permission disabled. This issue has been addressed in version 6.2. Users are advised to upgrade. Users unable to upgrade may enable the `Invitations are required for joining this organization` organization permission to prevent this issue.

Categories

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.05%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: zulip zulip
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-28623?
CVE-2023-28623 has been scored as a medium severity vulnerability.
How to fix CVE-2023-28623?
To fix CVE-2023-28623, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-28623 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-28623 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-28623?
CVE-2023-28623 affects zulip zulip.
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