Low severity · published Jul 10, 2026
CVE-2026-55671
ZITADEL: Server-Side Request Forgery (SSRF) and Denylist Bypass in Outgoing HTTP Components
2.3
CVSS
0.4%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZI
zitadel · zitadel
< 4.15.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55671
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55671
github.com
https://github.com/zitadel/zitadel/commit/b6f78086913b8d916bce9ab2e049ab0d84f947fd
github.com
https://github.com/zitadel/zitadel/releases/tag/v4.15.2
github.com
https://github.com/zitadel/zitadel/security/advisories/GHSA-29jh-8cfq-rr8x
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