CVE-2020-10187: Exposure of Sensitive Information to an Unauthorized Actor in Doorkeeper

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-05-04 · updated 2026-06-17
Weakness: CWE-862

Description

Doorkeeper version 5.0.0 and later contains an information disclosure vulnerability that allows an attacker to retrieve the client secret only intended for the OAuth application owner. After authorizing the application and allowing access, the attacker simply needs to request the list of their authorized applications in a JSON format (usually GET /oauth/authorized_applications.json). An application is vulnerable if the authorized applications controller is enabled.

Affected products

doorkeeper-gem doorkeeper: from 5.0.0 before 5.0.3; from 5.1.0 before 5.1.1; from 5.2.0 before 5.2.5; from 5.3.0 before 5.3.2 — fixed in 5.0.3, 5.1.1, 5.2.5, 5.3.2
Rubygems Doorkeeper: from 5.0.0 before 5.0.3; from 5.1.0 before 5.1.1; from 5.2.0 before 5.2.5; from 5.3.0 before 5.3.2; 5.0.0, 5.0.1, 5.0.2, 5.1.0, 5.2.0, 5.2.1 (+5) — fixed in 5.0.3, 5.1.1, 5.2.5, 5.3.2

How to fix

Upgrade to a fixed version: doorkeeper-gem doorkeeper 5.0.3, 5.1.1, 5.2.5, 5.3.2; Rubygems Doorkeeper 5.0.3, 5.1.1, 5.2.5, 5.3.2. Check the vendor advisory for mitigations.

References

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