# DotVVM missing authorization in AuthorizeActionFilter

Source: https://junglewise.ai/threats/dotvvm-missing-authorization-in-authorizeactionfilter-d8ca4ac8  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-19. Updated: 2026-06-19  
License: CC BY 4.0 with a link back

Severity: critical · CVSS 9.2 · Published 2026-06-19

DotVVM is a web framework for building ASP.NET applications. A critical flaw exists where the security filter intended to restrict access to authorized users fails to perform any checks. This allows any user to bypass intended security restrictions and access protected parts of an application without needing to log in or provide credentials.

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Critical severity, with a CVSS score of 9.2, published 19 June 2026.

**Which products and versions are affected?** riganti DotVVM < 4.2.11, > 4.3.0-preview01-final, < 4.3.15, >= 5.0.0-preview01-final, < 5.0.0-preview09-final.

**Is there a fix for This vulnerability?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is This vulnerability attacked?** It is attacked over the network, in a software library.

**Am I affected?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A vulnerability classified as Missing Authorization (CWE-862) exists in DotVVM's AuthorizeActionFilter class. The component fails to implement any actual authorization logic, effectively acting as a no-op filter. An unauthenticated attacker can reach protected endpoints over the network without any specific exploit complexity, as the filter does not validate the user's identity or permissions. This results in a complete bypass of intended access controls. The issue is resolved in versions 4.2.11, 4.3.15, and 5.0.0-preview09. A workaround is to use the AuthorizeAttribute instead.

## Affected products

- riganti DotVVM < 4.2.11, > 4.3.0-preview01-final, < 4.3.15, >= 5.0.0-preview01-final, < 5.0.0-preview09-final

## Timeline

- 2026-06-18: disclosed
- 2026-06-19: advisory

## References

- [https://github.com/riganti/dotvvm/security/advisories/GHSA-c8qj-jx8j-fg2w](https://github.com/riganti/dotvvm/security/advisories/GHSA-c8qj-jx8j-fg2w)
- [https://api.github.com/repos/riganti/dotvvm/security-advisories/GHSA-c8qj-jx8j-fg2w](https://api.github.com/repos/riganti/dotvvm/security-advisories/GHSA-c8qj-jx8j-fg2w)