{"cve":"CVE-2026-79662","nvd":{"published":"2026-08-25T12:16:31.470","modified":"2026-08-31T20:50:15.927","status":"Deferred","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_v4":{"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","score":8.8},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N","score":8.0},"cwes":["CWE-601"],"references":["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"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:50:17.453294893+00:00"},"epss":{"cve":"CVE-2026-79662","score":0.00321,"percentile":0.25109,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-p64j-f4x9-wq66","url":"https://osv.dev/vulnerability/GHSA-p64j-f4x9-wq66","summary":"Ech0's OAuth redirect URI validation ignores path component, enables exchange-code theft","modified":"2026-08-27T04:10:27.830496045Z","packages":[{"ecosystem":"Go","name":"github.com/lin-snow/Ech0","purl":"pkg:golang/github.com/lin-snow/Ech0","ranges":["<1.4.8-0.20260503040728-a7e8b8e84bd1"],"fixed":["1.4.8-0.20260503040728-a7e8b8e84bd1"]}]},{"id":"GO-2026-5531","url":"https://osv.dev/vulnerability/GO-2026-5531","summary":"Ech0's OAuth redirect URI validation ignores path component, enables exchange-code theft in github.com/lin-snow/ech0","modified":"2026-08-27T04:10:27.830496045Z","packages":[{"ecosystem":"Go","name":"github.com/lin-snow/ech0","purl":"pkg:golang/github.com/lin-snow/ech0","ranges":["<1.4.8-0.20260503040728-a7e8b8e84bd1"],"fixed":["1.4.8-0.20260503040728-a7e8b8e84bd1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}