CVE-2021-43791

    Dashboard / Vulnerabilities / CVE-2021-43791

    CVE-2021-43791

    Published: 2 Dec 2021Last Modified: 7 Aug 2026

    Summary:

    Details: 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.

    References: https://github.com/zulip/zulip/security/advisories/GHSA-wj76-pcqr-mf9f, https://github.com/zulip/zulip/commit/a014ef75a3a0ed7f24ebb157632ba58751e732c6

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: GIT

    Events:

    Introduced- 0
    Fixed -ae000bfdbaf428cb1f7164bab0668111e14d2304

    Affected versions

    4.7

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    CVE-2021-43791 | CVE-DB