# CVE-2026-58491: Warpgate cross-site scripting and open redirect in SSO handler

Source: https://junglewise.ai/threats/cve-2026-58491-warpgate-is-an-open-source-ssh-https-and-mysql-bastion-host-for  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-21. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-58491 · Severity: critical · CVSS 9.3 · Published 2026-09-21

Warpgate is an open source bastion host that provides centralized access control for SSH, HTTPS, and MySQL connections. An attacker can craft a malicious login URL that, when clicked by a victim who completes single sign-on, executes JavaScript in the authenticated Warpgate session or redirects to an attacker-controlled site. This allows attackers to steal session credentials, impersonate users, or perform unauthorized administrative actions.

Technologies: [Warp Tech Warpgate](https://junglewise.ai/threats/technologies/warp-tech-warpgate). Vendors: [Warp Tech](https://junglewise.ai/threats/vendors/warp-tech).

## Quick answers

**Is CVE-2026-58491 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-58491 being exploited in the wild.

**How severe is CVE-2026-58491?** Critical severity, with a CVSS score of 9.3, published 21 September 2026.

**Which products and versions are affected?** Warp Tech Warpgate before 0.25.5.

**Is there a fix for CVE-2026-58491?** A patch was published on 2026-06-18: Version 0.25.5 released with HTML escaping fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-58491 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-58491?** Check whether you run Warp Tech Warpgate at an affected version. 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

The vulnerability is a stored cross-site scripting (XSS) and open redirect flaw in the SSO endpoints. The /@warpgate/api/sso/providers/:name/start endpoint stores an attacker-controlled "next" parameter, which is later inserted without HTML escaping into responses generated by the SSO return handler in warpgate-protocol-http/src/api/sso_provider_list.rs. An unauthenticated attacker can craft a link containing malicious JavaScript, and when an authenticated user follows it, the code executes in their browser with access to user and (if applicable) administrator APIs.

## Affected products

- Warp Tech Warpgate before 0.25.5

## Timeline

- 2026-09-21: disclosed
- 2026-06-18: patched: Version 0.25.5 released with HTML escaping fix

## References

- [https://github.com/warp-tech/warpgate/commit/eab0548f018d95b5f96f8e913527000e05ed93a2](https://github.com/warp-tech/warpgate/commit/eab0548f018d95b5f96f8e913527000e05ed93a2)
- [https://github.com/warp-tech/warpgate/releases/tag/v0.25.5](https://github.com/warp-tech/warpgate/releases/tag/v0.25.5)

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