Open Redirect in Ech0 (CVE-2026-79662)
Summary
Vulnerability in Ech0 (CVE-2026-79662). Confidential information can be exposed externally. Exploitable via POST /api/auth/exchange. Mitigation: upgrade to 4.7.3 or later.
Original description
The description as published by the source.
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.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-79662 has been found in Ech0.
Attackers can target a specific entry point like POST /api/auth/exchange over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 8.0/10.
What to do: upgrade Ech0 to 4.7.3 or later.
If unsure, ask your IT team or search "Ech0 CVE-2026-79662" on the vendor's site.
CVE-2026-79662 (Ech0) — CWE-601 / CVSS v3 8.0
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: POST /api/auth/exchange
Patched: 4.7.3 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-601) exists in Ech0. Attackers reach the vulnerable code path via POST /api/auth/exchange without authentication.
Check the vendor advisory for the affected versions of Ech0. Attack surface: POST /api/auth/exchange.
Severity: High (CVSS 8.0/10). Confidential information can be exposed externally.
Update to 4.7.3.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /api/auth/exchange requests with malformed payloads or SQL meta-characters. Run grep -r 'Ech0' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Ech0' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Ech0を grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /api/auth/exchange' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /api/auth/exchangeへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade Ech0 to 4.7.3ステージング環境で 4.7.3 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /api/auth/exchange on staging to confirm patch closes the vectorパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory vulncheck.com
- advisory github.com
- package github.com
- web github.com
- web github.com