6.8

CVE-2021-3827: redhat keycloak Improper Authentication

Modified
AliasesGHSA-4pc7-vqv5-5r3v
Published 23-08-2022Last modified 03-08-2024

Vulnerability summary

CVE-2021-3827 is a medium (CVSS 6.8) Improper Authentication vulnerability in redhat keycloak. EPSS estimates a 1.11% chance of exploitation in the next 30 days, higher than 65.9% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 6.8, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.8/10
010
Medium · v3.1 (NVD)
EPSS score
1.11%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2
RHSA-2022:0151RHSA-2022:0152

Timeline

  1. 23-08-2022
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

A flaw was found in keycloak, where the default ECP binding flow allows other authentication flows to be bypassed. By exploiting this behavior, an attacker can bypass the MFA authentication by sending a SOAP request with an AuthnRequest and Authorization header with the user's credentials. The highest threat from this vulnerability is to confidentiality and integrity.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

1.11%

Chance of exploitation in the next 30 days

Percentile

66%

Versus all other CVEs

30-day change

Increase +0.02 pp

From 1.09% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Redhat3 products
Org.keycloak1 product
  • keycloak-saml-core< 18.0.0

2 vendors · 4 products

References

6 links