Vulnerability in Logto (CVE-2026-63203)
Summary
Vulnerability in Logto (CVE-2026-63203). Confidential information can be exposed externally. Exploitable via GET /api/my-account/identities/{target}/access-token.
Original description
The description as published by the source.
Logto is the modern, open-source auth infrastructure for SaaS and AI apps. From 1.31.0 until 1.42.0, the Account API handlers in packages/core/src/routes/account/third-party-tokens.ts allow a caller holding a same-user access token with only the openid scope to retrieve stored social or enterprise SSO provider access tokens through GET /api/my-account/identities/{target}/access-token or GET /api/my-account/sso-identities/{connectorId}/access-token. The handlers authenticate the user but do not require the identities scope that protects neighboring identity-detail operations, bypassing the intended Account API consent boundary. Exploitation requires federated token-set storage to be enabled and the affected user to have authenticated through a supported connector. A low-trust application can use the disclosed provider token against upstream APIs within that token's granted scopes. This issue is fixed in version 1.42.0.
Source: NIST National Vulnerability Database NVD
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-2026-63203 has been found in Logto.
Attackers can target a specific entry point like GET /api/my-account/identities/{target}/access-token over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 7.6/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Logto CVE-2026-63203" on the vendor's site.
CVE-2026-63203 (Logto) — CWE-862 / CVSS v3 7.6
Attack vector: remote (network-reachable)
Attack surface: GET /api/my-account/identities/{target}/access-token / GET /api/my-account/sso-identities/{connectorId}/access-token.
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 Logto. Attackers reach the vulnerable code path via GET /api/my-account/identities/{target}/access-token.
Check the vendor advisory for the affected versions of Logto. Attack surface: GET /api/my-account/identities/{target}/access-token / GET /api/my-account/sso-identities/{connectorId}/access-token..
Severity: High (CVSS 7.6/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual GET /api/my-account/identities/{target}/access-token requests with malformed payloads or SQL meta-characters. Run grep -r 'Logto' . 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 'Logto' . | 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
Logto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 'GET /api/my-account/identities/{target}/access-token' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/my-account/identities/{target}/access-token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。 -
3Post-deployment verification verify
Replay attack against GET /api/my-account/identities/{target}/access-token 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。