Vulnerability in github.com/zitadel/zitadel (CVE-2026-56668)
Summary
Vulnerability in github.com/zitadel/zitadel (CVE-2026-56668). Confidential information can be exposed externally. Mitigation: upgrade to 4.15.3 or later.
Original description
The description as published by the source.
Summary
A vulnerability in ZITADEL’s OAuth2 Token Exchange endpoint allows an authenticated user or client to exchange a low-privilege access token for a token with elevated permissions at a completely different application. This bypasses the intended authorization and separation policies configured within ZITADEL.
Impact
ZITADEL enables administrators to restrict token issuance based on client permissions, project roles, and specific scopes. Due to a missing verification step during the Token Exchange flow (urn:ietf:params:oauth:grant-type:token-exchange), ZITADEL fails to validate whether the incoming access token belongs to or is authorized for the client initiating the exchange. Additionally, ZITADEL does not enforce that the newly requested scopes must stay within the boundaries of the original token's scopes.
An attacker with valid access to a low-privilege application can exploit this behavior by sending a token exchange request to a highly-privileged target application. This allows them to obtain administrative project roles, access sensitive profile data, or gain unauthorized access to other applications across the system. If public clients (which do not require client secrets) are used, this risk increases significantly as it requires no client authentication.
Affected Versions
Systems running one of the following versions are affected:
- 4.x:
4.0.0through4.15.2(including RC versions) - 3.x:
3.0.0through3.4.12(including RC…
Source: NIST National Vulnerability Database 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-2026-56668 has been found in github.com/zitadel/zitadel.
Confidential information can be exposed externally. CVSS score: 8.1/10.
What to do: upgrade github.com/zitadel/zitadel to 4.15.3 or later.
If unsure, ask your IT team or search "github.com/zitadel/zitadel CVE-2026-56668" on the vendor's site.
CVE-2026-56668 (github.com/zitadel/zitadel) — CWE-862 / CVSS v3 8.1
Attack vector: remote (network-reachable) / no user interaction
Patched: 4.15.3 — 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-862) exists in github.com/zitadel/zitadel.
Check the vendor advisory for the affected versions of github.com/zitadel/zitadel.
Severity: High (CVSS 8.1/10). Confidential information can be exposed externally.
Update to 4.15.3.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'github.com/zitadel/zitadel' . 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 'github.com/zitadel/zitadel' . | 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
github.com/zitadel/zitadelを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade github.com/zitadel/zitadel to 4.15.3ステージング環境で 4.15.3 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を含めること。
-
3Post-deployment verification verify
Confirm patched version is live in production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。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- web github.com
- web github.com
- web github.com
- web nvd.nist.gov
- web github.com