CVE-2019-9837

Doorkeeper::OpenidConnect (aka the OpenID Connect extension for Doorkeeper) 1.4.x and 1.5.x before 1.5.4 has an open redirect via the redirect_uri field in an OAuth authorization request (that results in an error response) with the 'openid' scope and a prompt=none value. This allows phishing attacks against the authorization flow.

Published: 2019-03-21 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-9837 is rated Moderate Risk (44.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.36%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2019-9837

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-03 0.28% 0.36% +0.08%
2 2025-03-17 0.09% 0.28% +0.19%
3 2023-03-07 — 0.09% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-9837

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]
5.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 4.9 [email protected]

Weakness enumeration for CVE-2019-9837

GitHub Security Advisory for CVE-2019-9837

GHSA-vv4c-g6q7-p3q7 · Severity: medium · Ecosystem: rubygems — Doorkeeper-openid_connect contains Open Redirect

OS Trackers for CVE-2019-9837

vendor priority summary link
debian not yet assigned CVE-2019-9837 not yet assigned priority: Debian including 1 source packages (ruby-doorkeeper-openid-connect), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2019-9837
ubuntu medium CVE-2019-9837 medium priority: Ubuntu including 1 source packages (ruby-doorkeeper-openid-connect), 6 status rows across 6 suites (bionic, cosmic, disco, trusty, upstream, xenial): DNE 2, not-affected 2, needs-triage 1, released 1. https://ubuntu.com/security/CVE-2019-9837

Affected software / configurations for CVE-2019-9837

Vendor Product Version Raw CPE
openid openid_connect >= 1.4.0, < 1.5.4 cpe:2.3:a:openid:openid_connect:*:*:*:*:*:doorkeeper:*:*

References for CVE-2019-9837

cvelogic Threat Intelligence