# CVE-2026-55671: ZITADEL SSRF and denylist bypass in outgoing HTTP components

Source: https://junglewise.ai/threats/cve-2026-55671-zitadel-ssrf-and-denylist-bypass-in-outgoing-http-components  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-10. Updated: 2026-07-10  
License: CC BY 4.0 with a link back

CVE-2026-55671 · Severity: medium · CVSS 4 · Published 2026-07-10

ZITADEL, an open-source identity management platform, is vulnerable to a security flaw where certain features—such as notification webhooks and logout processes—can be manipulated to send unauthorized requests to internal systems. An attacker with low-level access could use this to probe the organization's internal network, scan for open ports, or interact with sensitive internal services that are not intended to be public. This could lead to the exposure of internal network architecture or unauthorized access to internal infrastructure.

Technologies: [github.com/zitadel/zitadel (Go)](https://junglewise.ai/threats/technologies/github-com-zitadel-zitadel), [ZITADEL](https://junglewise.ai/threats/technologies/zitadel). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [ZITADEL](https://junglewise.ai/threats/vendors/zitadel).

## Quick answers

**Is CVE-2026-55671 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-55671 being exploited in the wild.

**How severe is CVE-2026-55671?** Medium severity, with a CVSS score of 4, published 10 July 2026.

**Which products and versions are affected?** github.com/zitadel/zitadel (Go) < 1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2, SEMVER:introduced=0,fixed=1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2; ZITADEL 3.0.0 - 3.4.11, 4.0.0 - 4.15.1, 4.0.0-rc.1 through 4.15.1; 3.0.0 through 3.4.11.

**Is there a fix for CVE-2026-55671?** Yes. github.com/zitadel/zitadel (Go): upgrade to 1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-55671 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-55671?** Check whether you run github.com/zitadel/zitadel (Go) or ZITADEL 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.

## How to fix

- github.com/zitadel/zitadel (Go): upgrade to 1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2 or later

  ```sh
  go get github.com/zitadel/zitadel@v1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2
  ```


## Technical details

A Server-Side Request Forgery (SSRF) vulnerability exists in ZITADEL's outgoing HTTP components, specifically within HTTP notification channels, OIDC BackChannel Logout, and SAML metadata URL fetches. The application fails to consistently validate user-supplied URLs against a protected denylist, and the existing denylist mechanism was found to be bypassable via DNS rebinding, HTTP redirects, and protocol downgrades (HTTPS to HTTP). An authenticated attacker with low privileges can provide malicious URLs pointing to loopback addresses, internal IP ranges, or cloud metadata services (IMDS). This allows for internal network mapping and interaction with unauthorized internal services. The fix, introduced in version 4.15.2, implements a hardened HTTP client with DNS rebinding protection and a unified denylist.

## Affected products

- ZITADEL ZITADEL 4.0.0-rc.1 through 4.15.1; 3.0.0 through 3.4.11

## Identifiers

- CVE-2026-55671
- GHSA-29jh-8cfq-rr8x
- GO-2026-5059

## Timeline

- 2026-06-15: patched: Fix committed to repository
- 2026-06-17: advisory: GitHub Security Advisory published and version 4.15.2 released
- 2026-07-10: disclosed: CVE published to NVD

## References

- [https://github.com/zitadel/zitadel/commit/b6f78086913b8d916bce9ab2e049ab0d84f947fd](https://github.com/zitadel/zitadel/commit/b6f78086913b8d916bce9ab2e049ab0d84f947fd)
- [https://github.com/zitadel/zitadel/releases/tag/v4.15.2](https://github.com/zitadel/zitadel/releases/tag/v4.15.2)
- [https://github.com/zitadel/zitadel/security/advisories/GHSA-29jh-8cfq-rr8x](https://github.com/zitadel/zitadel/security/advisories/GHSA-29jh-8cfq-rr8x)

## Related threats

- [ZITADEL missing authorization in Login V2 device authorization](https://junglewise.ai/threats/cve-2026-119129-zitadel-3-0-0-through-3-4-15-and-4-0-0-before-4-19-5-contains-a)
- [ZITADEL authentication bypass in Login V2 UI](https://junglewise.ai/threats/cve-2026-119128-zitadel-4-0-0-before-4-19-5-contains-an-authentication-bypass)
- [ZITADEL Login V2 host header injection in password reset](https://junglewise.ai/threats/cve-2026-119127-zitadel-4-0-0-before-4-19-5-contains-a-host-header-injection)
- [ZITADEL privilege escalation in OIDC token exchange](https://junglewise.ai/threats/cve-2026-109374-zitadel-3-0-0-before-4-19-2-contains-a-privilege-escalation)
- [ZITADEL authentication bypass in Login V2 UI](https://junglewise.ai/threats/cve-2026-109373-zitadel-3-0-0-before-4-19-2-contains-an-authentication-bypass)