CVE-2021-43791 Ineffective expiration validation for invitation links in Zulip
Attackers can register accounts using expired invitation links due to missing validation in the registration endpoint, allowing unauthorized access.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-43791?
CVE-2021-43791 is a medium-severity vulnerability in zulip, published on 2 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Zulip is an open source group chat application that combines real-time chat with threaded conversations. In affected versions expiration dates on the confirmation objects associated with email invitations were not enforced properly in the new account registration flow. A confirmation link takes a user to the check_prereg_key_and_redirect endpoint, before getting redirected to POST to /accounts/register/. The problem was that validation was happening in the check_prereg_key_and_redirect part and not in /accounts/register/ - meaning that one could submit an expired confirmation key and be able to register. The issue is fixed in Zulip 4.8. There are no known workarounds and users are advised to upgrade as soon as possible.
Weakness: CWE-613
Which versions are affected by CVE-2021-43791?
It affects 1 product.
Products include Zulip Zulip.
How do I fix CVE-2021-43791?
No fix has been published for CVE-2021-43791 yet. Limit exposure of the affected software until one is available.
Is CVE-2021-43791 being exploited?
There is no known exploitation of CVE-2021-43791 in the wild and no public exploit code.
Other vulnerabilities in zulip
- CVE-2021-43799 RabbitMQ exposes ports with weak default secrets in Zulip Server
- CVE-2022-35962 Crafted link in Zulip message can cause disclosure of credentials
- CVE-2016-4427 Auth bypass in zulip
- CVE-2021-3866 Cross-site Scripting (XSS) - Stored in zulip/zulip
- CVE-2023-28623 Unauthorized user can register an account in specific configurations in Zulip
Sources
Also known as GHSA-wj76-pcqr-mf9f.