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.
https://github.com/zitadel/zitadel/security/advisories/GHSA-29jh-8cfq-rr8x
https://github.com/zitadel/zitadel/releases/tag/v4.15.2
https://github.com/zitadel/zitadel/commit/b6f78086913b8d916bce9ab2e049ab0d84f947fd
Published: 2026-07-10
Updated: 2026-07-14
Base Score: 6.4
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N
Severity: Medium
Base Score: 9.1
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity: Critical
Base Score: 2.3
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
Severity: Low
EPSS: 0.00252