Horizon Alert
Summary of the vulnerability and why it matters
This advisory concerns a vulnerability in SOGo groupware software that could allow unauthenticated attackers to reset user passwords by repeatedly guessing answers to security questions. The issue arises from a lack of proper controls on the password recovery feature, potentially enabling unauthorized account access. While the primary concern is to confirm if your organization uses this software, understanding its potential for account takeover is important for assessing risk.
- Attackers can bypass account security.
- It enables unauthorized account takeover.
- Confirm relevance and assess exposure.
Attack Path
How an attacker could exploit the issue
An attacker can target an exposed SOGo web interface, which is often publicly accessible for remote user access. By repeatedly guessing secret-question answers through a specific recovery endpoint, an attacker can bypass security measures like account lockouts or rate limiting. If successful, this allows them to obtain a recovery token, reset any account's password without prior credentials, and gain full control of the account if two-factor authentication is not enabled.
- Accessible via network without authentication.
- Guess secret answers at password recovery endpoint.
- Risk of full account takeover.
Live Threat
Current exploitation, exposure, and threat context
This vulnerability could allow an unauthenticated attacker to reset account passwords through the password recovery feature. By repeatedly guessing secret question answers, an attacker could bypass security measures and obtain a recovery token, leading to a full account takeover for accounts that do not have multi-factor authentication enabled.
- Account passwords and access.
- Repeatedly guessing secret questions.
- Full account takeover is possible.
Operational Fix
Recommended remediation, mitigation, and detection steps
For SOGo, the platform or application owner is responsible for addressing this vulnerability, as it affects a groupware server often exposed externally. The first practical step is to identify all SOGo instances, confirm their internet reachability and business criticality, and then work with the accountable owner to plan remediation, potentially involving vendor coordination or temporary risk reduction measures if direct patching is not immediately feasible.
- Application or platform owners should manage this issue.
- Verify internet-facing instances and their criticality.
- Coordinate with vendors and plan remediation.
