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.

Project Subscriptions

Vendors Products
Lin-snow Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 25 Aug 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 25 Aug 2026 14:00:00 +0000

Type Values Removed Values Added
First Time appeared Lin-snow
Lin-snow ech0
Vendors & Products Lin-snow
Lin-snow ech0

Tue, 25 Aug 2026 11:45:00 +0000

Type Values Removed Values Added
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.
Title Ech0 before 4.7.3 OAuth Redirect URI Validation Bypass
First Time appeared Ech0
Ech0 ech0
Weaknesses CWE-601
CPEs cpe:2.3:a:ech0:ech0:*:*:*:*:*:*:*:*
Vendors & Products Ech0
Ech0 ech0
References
Metrics cvssV3_1

{'score': 8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N'}

cvssV4_0

{'score': 8.8, 'vector': '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'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-25T14:51:03.397Z

Reserved: 2026-08-25T11:09:11.171Z

Link: CVE-2026-79662

cve-icon Vulnrichment

Updated: 2026-08-25T14:50:26.027Z

cve-icon NVD

Status : Received

Published: 2026-08-25T12:16:31.470

Modified: 2026-08-25T15:16:45.733

Link: CVE-2026-79662

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-25T13:45:04Z

Weaknesses