CVE-2026-105208
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.08%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.08% probability · 0th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-649
- Source
- disclosure@vulncheck.com
EPSS moved from 0.1% on 5 October 2026 to 0.1% on 26 October 2026.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.