5.3

CVE-2021-3424: redhat single_sign-on Improper Authentication

CVSS: 5.3v3.1MediumModified
AliasesGHSA-pf38-cw3p-22q9
Published 01-06-2021Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-3424 is a medium (CVSS 5.3) Improper Authentication vulnerability in redhat single_sign-on. EPSS estimates a 0.77% chance of exploitation in the next 30 days, higher than 54.8% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.77%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3
RHSA-2021:2063RHSA-2021:2064RHSA-2021:2065

Timeline

  1. 01-06-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

A flaw was found in keycloak as shipped in Red Hat Single Sign-On 7.4 where IDN homograph attacks are possible. A malicious user can register himself with a name already registered and trick admin to grant him extra privileges.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.77%

Chance of exploitation in the next 30 days

Percentile

55%

Versus all other CVEs

30-day change

0.00 pp

From 0.77% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.77%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Org.keycloak1 product
  • keycloak-services< 18.0.0
Redhat1 product

2 vendors · 2 products

References

3 links