Impact
The vulnerability allows any authenticated user to gain access to arbitrary accounts by setting a specially crafted email address. This vulnerability impacts all instances that have not set an explicit email domain name allowlist. Note that whereas neither administrators nor targeted users are notified of a change, an attacker will need to control an account. The default settings require administrators to validate newly created accounts.
Patches
The problem has been patched. Users should upgrade to at least version 4.2.0.
Workarounds
Enabling an email domain allow list (from Sysconfig panel, Security tab) will completely resolve the issue.
References
This vulnerability was discovered and responsibly disclosed by Anders Märak Leffler (@anargam).
For more information
If you have any questions or comments about this advisory:
anargam Analyst
NicolasCARPi Analyst
Impact
The vulnerability allows any authenticated user to gain access to arbitrary accounts by setting a specially crafted email address. This vulnerability impacts all instances that have not set an explicit email domain name allowlist. Note that whereas neither administrators nor targeted users are notified of a change, an attacker will need to control an account. The default settings require administrators to validate newly created accounts.
Patches
The problem has been patched. Users should upgrade to at least version 4.2.0.
Workarounds
Enabling an email domain allow list (from Sysconfig panel, Security tab) will completely resolve the issue.
References
This vulnerability was discovered and responsibly disclosed by Anders Märak Leffler (@anargam).
For more information
If you have any questions or comments about this advisory: