Vulnerability Description
Ech0 through 4.5.6 contains an OAuth redirect URI validation vulnerability in parseAndValidateClientRedirect (internal/service/auth/auth.go) that compares only the scheme and host of the client-supplied redirect_uri against the admin-configured allowlist, ignoring path, query, and fragment components. The redirect_uri is embedded into the signed state JWT at login time without validation. An attacker can craft a redirect_uri whose host matches an allowed origin but whose path is attacker-influenced; after the OAuth exchange the victim is redirected to that path with a one-time exchange code in the query string. If the code leaks (e.g., via Referer, analytics, or an open redirect on that host), the attacker can trade it at the public POST /api/auth/exchange endpoint for the victim's access and refresh tokens. Fixed in 4.7.3.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/lin-snow/Ech0/security/advisories/GHSA-p64j-f4x9-wq66
- https://www.vulncheck.com/advisories/ech0-before-oauth-redirect-uri-validation-b
- https://github.com/lin-snow/Ech0/security/advisories/GHSA-p64j-f4x9-wq66
FAQ
What is CVE-2026-79662?
CVE-2026-79662 is a vulnerability with a CVSS score of 8.0 (HIGH). Ech0 through 4.5.6 contains an OAuth redirect URI validation vulnerability in parseAndValidateClientRedirect (internal/service/auth/auth.go) that compares only the scheme and host of the client-suppli...
How severe is CVE-2026-79662?
CVE-2026-79662 has been rated HIGH with a CVSS base score of 8.0/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-79662?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.