All Vulnerability Reports

CVE-2021-22119: Denial-of-Service (DoS) attack via initiation of Authorization Request in Spring Security OAuth 2.0 Client Web and WebFlux Application




Spring by VMware


Spring Security versions 5.5.x prior to 5.5.1, 5.4.x prior to 5.4.7, 5.3.x prior to 5.3.10 and 5.2.x prior to 5.2.11 are susceptible to a Denial-of-Service (DoS) attack via the initiation of the Authorization Request in an OAuth 2.0 Client Web and WebFlux application. A malicious user or attacker can send multiple requests initiating the Authorization Request for the Authorization Code Grant, which has the potential of exhausting system resources using a single session or multiple sessions. This vulnerability exposes OAuth 2.0 Client applications that use HttpSessionOAuth2AuthorizationRequestRepository (Servlet) and WebSessionOAuth2ServerAuthorizationRequestRepository (Reactive).

Affected VMware Products and Versions

Severity is critical unless otherwise noted.

  • Spring Security
    • 5.5.x prior to 5.5.1
    • 5.4.x prior to 5.4.7
    • 5.3.x prior to 5.3.10
    • 5.2.x prior to 5.2.11


Users of affected versions should upgrade to the following versions:

  • Spring Security
    • 5.5.1
    • 5.4.7
    • 5.3.10
    • 5.2.11


This issue was identified and responsibly reported by Craig Andrews (



2021-06-28: Initial vulnerability report published.