CVE-2026-63203EPSS p21.8%

CVE-2026-63203CVE-2026-63203

Description

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.

Scoring

CVSS 7.6 ()
VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N
EPSS0.31% probability of exploitation · percentile 21.8% · 2026-10-05T12:00:23Z
Last modified2026-09-24
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.