CVE-2021-20195: redhat keycloak Improper Input Validation
Vulnerability summary
CVE-2021-20195 is a critical (CVSS 9.6) Improper Input Validation vulnerability in redhat keycloak. EPSS estimates a 1.25% chance of exploitation in the next 30 days, higher than 68.9% of scored vulnerabilities.
Timeline
- 28-05-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
A flaw was found in keycloak in versions before 13.0.0. A Self Stored XSS attack vector escalating to a complete account takeover is possible due to user-supplied data fields not being properly encoded and Javascript code being used to process the data. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
CVSS metrics
3 scores · 2 sources · 2 versions- OSV · MavenEcosystem advisory · calculated9.6CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EPSS trend
Probability
1.25%
Chance of exploitation in the next 30 days
Percentile
69%
Versus all other CVEs
30-day change
0.00 pp
From 1.25% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-20Improper Input ValidationThe product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
- CWE-116Improper Encoding or Escaping of OutputThe product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
Affected systems
Org.keycloak1 product
- keycloak-core< 13.0.0
Redhat1 product
- keycloak< 12.0.3
2 vendors · 2 products
