CVE-2026-41839: Spring Framework Escalation via Session Fixation in WebFlux
(updated )
A WebFlux application with a compromised subdomain (for example, compromised via cross-site scripting (XSS)) is vulnerable to an escalation attack exchanging a known session ID for that of an authenticated user.
Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
References
- github.com/advisories/GHSA-4hfh-6x8g-gwpp
- github.com/spring-projects/spring-framework/commit/b8ddd2c690fe3f00bb5e3d9f913a37504aab49a0
- github.com/spring-projects/spring-framework/commit/d72da90d3a562632e2b565113813f7b4a31f8717
- github.com/spring-projects/spring-framework/issues/36742
- github.com/spring-projects/spring-framework/issues/36743
- github.com/spring-projects/spring-framework/releases/tag/v6.2.19
- github.com/spring-projects/spring-framework/releases/tag/v7.0.8
- nvd.nist.gov/vuln/detail/CVE-2026-41839
- spring.io/security/cve-2026-41839
Code Behaviors & Features
Detect and mitigate CVE-2026-41839 with GitLab Dependency Scanning
Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →