Skip to main content
Public proof of conceptFix available

CVE-2021-3754

A public proof of concept exists; no exploitation attested.

  • Published2022-08-26
  • WeaknessCWE-20

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A flaw was found in keycloak where an attacker is able to register himself with the username same as the email ID of any existing user. This may cause trouble in getting password recovery email in case the user forgets the password.

Timeline

dates in UTC
  1. 2022-08-2616:15CVE publishedNVD
  2. 2026-10-2319:23First public proof of conceptPoC-in-GitHub

Versions per branch

NVD · OSV
Redhat keycloak
BranchAffectedFixed in
—all versionsno fix published
Redhat single sign-on
BranchAffectedFixed in
7.0= 7.0no fix published
keycloak-services
BranchAffectedFixed in
24.0< 24.0.124.0.1

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

Detection

read 2026-11-01 01:02 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Published
2022-08-26
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-4vc8-pg5c-vg4x

Frequently asked questions

What is CVE-2021-3754?

A flaw was found in keycloak where an attacker is able to register himself with the username same as the email ID of any existing user. This may cause trouble in getting password recovery email in case the user forgets the password.

Is CVE-2021-3754 actively exploited?

Active exploitation of CVE-2021-3754 has not been confirmed. Its EPSS score was 2.2% on 2026-11-09, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-3754?

CVE-2021-3754 has a CVSS v3 base score of 5.3 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Hear about the next vulnerability in your software

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, November 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record