Vulnerability · Published Oct 4, 2026 · Assigned by VulnCheck

CVE-2026-105208ZITADEL before 4.17.3 Session Hijacking via Forgeable IdP Intent Tokens

High 7.7

In plain English

A high-severity security flaw in zitadel from zitadel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 0% of all known vulnerabilities).

Severity (CVSS 3.1)7.7High

Exploit odds (30 days)<0.1%top 99.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

ZITADEL 4.x before 4.17.3 and 3.x through 3.4.15 protects IdP intent tokens with unauthenticated, malleable encryption, allowing authenticated users to tamper with their own token so it is accepted for another user's external login intent. An attacker who predicts a victim's in-flight intent identifier and wins a timing race can call /v2/idp_intents or /v2/sessions to steal the victim's IdP tokens or hijack their session.

Affected products (as reported)

Vendor	Product	Versions
zitadel	zitadel	4.0.0 – before 4.17.3
zitadel	zitadel	3.0.0 – through 3.4.15

Weakness: CWE-649 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N

References

GitHub Security Advisory (GHSA-jh3m-cr2x-qp88) vendor-advisory
VulnCheck Advisory: ZITADEL before 4.17.3 Session Hijacking via Forgeable IdP Intent Tokens third-party-advisory