CVE-2020-11052 in Sorcery
Summary
by MITRE
In Sorcery before 0.15.0, there is a brute force vulnerability when using password authentication via Sorcery. The brute force protection submodule will prevent a brute force attack for the defined lockout period, but once expired, protection will not be re-enabled until a user or malicious actor logs in successfully. This does not affect users that do not use the built-in brute force protection submodule, nor users that use permanent account lockout. This has been patched in 0.15.0.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 10/15/2020
The vulnerability described in CVE-2020-11052 affects the Sorcery authentication library version 0.14.0 and earlier, specifically targeting the brute force protection mechanism implemented within the framework. This represents a critical flaw in the authentication security model where the system fails to maintain proper protection boundaries after temporary lockout periods expire. The issue stems from the design decision that allows the brute force protection to be automatically disabled once a lockout period concludes, requiring a successful login event to re-enable protection mechanisms. This creates a window of vulnerability where repeated failed authentication attempts can occur without effective mitigation, essentially undermining the core purpose of the brute force protection subsystem.
The technical implementation flaw lies in the protection module's state management and reset logic. When a user account is temporarily locked due to multiple failed authentication attempts, the system correctly implements the lockout period as intended. However, the subsequent behavior demonstrates a critical design oversight where the protection mechanism does not automatically re-enable itself after the lockout expires. Instead, the system waits for a legitimate login attempt to reactivate the protection, creating a race condition where malicious actors can exploit this gap to perform additional brute force attempts. This behavior violates fundamental security principles regarding access control and authentication state management.
From an operational impact perspective, this vulnerability creates significant risk for systems utilizing Sorcery with password authentication. Attackers can leverage the window between lockout expiration and protection re-enablement to conduct multiple failed login attempts without triggering additional protective measures. The vulnerability affects the core authentication flow and essentially renders the brute force protection ineffective for the duration of this window. This creates a substantial risk for credential stuffing attacks and password spraying techniques, where attackers can systematically attempt to guess valid credentials without facing the full protective measures that should be active. The issue is particularly concerning because it affects the fundamental security controls that are expected to protect against automated attack vectors.
The mitigation strategy for this vulnerability requires immediate upgrade to Sorcery version 0.15.0 or later, where the protection mechanism has been corrected to maintain proper state management. Organizations should also consider implementing additional authentication controls such as rate limiting at the network level, multi-factor authentication, and monitoring for unusual login patterns. This vulnerability aligns with CWE-307, which addresses improper restriction of excessive authentication attempts, and relates to ATT&CK technique T1110 which covers Brute Force attacks. Security teams should also review their authentication logs to identify potential exploitation attempts and implement enhanced monitoring for failed authentication patterns that could indicate brute force activity. The fix addresses the specific implementation flaw where the protection subsystem's state transition logic was not properly handling the automatic re-enablement of security controls after temporary lockout periods.