CVE-2026-56739 (GCVE-0-2026-56739)
Vulnerability from cvelistv5 – Published: 2026-09-24 15:20 – Updated: 2026-09-28 20:11
VLAI
EPSS
VEX
Title
Logto: SSRF via Webhooks and Custom OAuth2 Connector UserInfo Endpoint
Summary
Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.43.0, Logto fetches administrator-controlled outbound destinations without validating the address used for the connection. Webhook delivery in packages/core/src/libraries/hook/utils.ts can reach special-use and cloud metadata addresses. Custom OAuth2 connectors can use an attacker-selected userInfoEndpoint and forward the OAuth access token in the Authorization header, while OIDC connectors can fetch an attacker-selected jwksUri. The affected operations require tenant administrative configuration access, but they cross the server's network boundary and can expose internal data or upstream provider credentials. This issue is fixed in version 1.43.0.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-28 20:11 UTC
CWE
- CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/logto-io/logto/security/adviso… | x_refsource_CONFIRM |
| https://github.com/logto-io/logto/pull/9501 | x_refsource_MISC |
| https://github.com/logto-io/logto/commit/16f4b2e7… | x_refsource_MISC |
| https://github.com/logto-io/logto/releases/tag/v1.43.0 | x_refsource_MISC |
Impacted products
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"lastModified": "2026-09-28T21:17:18.067",
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