CVE-2020-27838

MEDIUM NUCLEI

Keycloak < 13.0.0 - Unauthenticated Information Disclosure via Client Registration Endpoint

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2020-27838. PoCs published by Cappricio-Securities. A Nuclei detection template is also available.

AI-analyzed exploit summary This repository contains a Python-based scanner for detecting CVE-2020-27838, a vulnerability in an unspecified target software. The tool checks for exposed endpoints and sensitive data (e.g., 'security-admin-console', 'secret') via HTTP requests. It includes features like Telegram notifications and output logging.

Description

A flaw was found in keycloak in versions prior to 13.0.0. The client registration endpoint allows fetching information about PUBLIC clients (like client secret) without authentication which could be an issue if the same PUBLIC client changed to CONFIDENTIAL later. The highest threat from this vulnerability is to data confidentiality.

Exploits (1)

nomisec SCANNER 2 stars
by Cappricio-Securities · poc
https://github.com/Cappricio-Securities/CVE-2020-27838

This repository contains a Python-based scanner for detecting CVE-2020-27838, a vulnerability in an unspecified target software. The tool checks for exposed endpoints and sensitive data (e.g., 'security-admin-console', 'secret') via HTTP requests. It includes features like Telegram notifications and output logging.

Classification
Scanner 90%
Attack Type
Info Leak
Complexity
Trivial
Reliability
Reliable
Target: Unspecified (likely a web application with exposed admin endpoints)
No auth needed
Prerequisites: Network access to the target URL · Python 3.x environment
devstral-2 · analyzed Feb 16, 2026 Full analysis →

Nuclei Templates (1)

KeyCloak - Information Exposure
MEDIUMby mchklt
Shodan: title:"keycloak" || http.title:"keycloak" || http.html:"keycloak" || http.favicon.hash:-1105083093
FOFA: title="keycloak" || icon_hash=-1105083093 || body="keycloak"

References (1)

Core 1
Core References
Issue Tracking, Vendor Advisory x_refsource_misc
https://bugzilla.redhat.com/show_bug.cgi?id=1906797

Scores

CVSS v3 6.5
EPSS 0.1794
EPSS Percentile 96.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Details

CWE
CWE-287
Status published
Products (3)
org.keycloak/keycloak-core 0 - 13.0.0Maven
redhat/keycloak < 13.0.0
redhat/single_sign-on 7.0
Published Mar 08, 2021
Tracked Since Feb 18, 2026