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Vulnerability record · CVE-2026-79662 · published 25 August 2026

CVE-2026-79662: Open redirect vulnerability

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.

8.8 CVSS 4.0 High EPSS 0.32% · top 77.4% CWE-601 · Open redirect Deferred
8.8CVSS 4.0 base score
0.32%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
3References
31 Aug 2026Last modified by NVD

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:4.0/AV:N/AC:H/AT:P/PR:N/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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

References

LinkTags
https://github.com/lin-snow/Ech0/security/advisories/GHSA-p64j-f4x9-wq66
https://www.vulncheck.com/advisories/ech0-before-oauth-redirect-uri-validation-bypass
https://github.com/lin-snow/Ech0/security/advisories/GHSA-p64j-f4x9-wq66

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Same products first, then exploited flaws of the same weakness class.

4.7CVE-2012-0518Oracle Fusion Middleware SSO open redirect flawOracle Fusion Middleware 10.1.4.3.0 contains an unspecified open redirect vulnerability in the Application Server Single Sign-On component, tracked a…KEVEPSS 4.7%analysed6.1CVE-2021-38000Google Chrome Android Intents input validation open redirectChrome on Android before 95.0.4638.69 fails to properly validate untrusted input passed through Intents, allowing a crafted HTML page to redirect the…KEVEPSS 4.9%analysed

Source: NIST National Vulnerability Database (record CVE-2026-79662), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.