Skip to main content

Boteraser | Website and Server Security Solutions

🛡️ CVE-2021-3754 — keycloak-services

🟢 CVSS 2.0 — Low ✅ No Known Exploit CWE-670 OSV
2.0
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Keycloak's improper input validation allows using email as username

Keycloak allows the use of email as a username and doesn't check that an account with this email already exists. That could lead to the unability to reset/login with email for the user. This is caused by usernames being evaluated before emails.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is high, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity none, availability low.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: High — the attacker first has to win a race, learn a secret or otherwise prepare the target.
  • Privileges required: None — an unauthenticated stranger can try it.
  • User interaction: None — nobody has to be tricked into anything.
  • Scope: Unchanged — the damage stays inside the vulnerable component.
  • Confidentiality impact: None.
  • Integrity impact: None.
  • Availability impact: Low — limited, and the attacker does not choose what is affected.

Weakness class

CVE-2021-3754 is classified as CWE-670: Always-Incorrect Control Flow Implementation. The control flow does not do what the logic intends, so a check never has the effect it appears to have.

Affected software

CVE-2021-3754 is recorded against 1 package.

  • org.keycloak:keycloak-services (fixed in 24.0.1)

Timeline and source

Published on 12 June 2024 and last revised on 20 December 2024. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

github.com (Web)
nvd.nist.gov (Advisory)
github.com (Web)
access.redhat.com (Web)
bugzilla.redhat.com (Web)
github.com (Package)

Other advisories for this package

org.keycloak:keycloak-services has other advisories on record. If you are patching this one, these are worth checking on the same host:

Same weakness in other software

These advisories are the same class of weakness (CWE-670: Always-Incorrect Control Flow Implementation) in other software:

Details

Severity LOW
CVSS Score 2.0
CVSS Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE CWE-670
Public Exploit ✅ No
Source OSV
Published 2024-06-12
Updated 2026-08-20
Modified 2024-12-20
Fix URL N/A

Affected Packages

Software From version Fixed in
org.keycloak:keycloak-services — 24.0.1

Similar Threats

Free Vulnerability Check

Is your site affected by CVE-2021-3754?

BotEraser helps you identify potentially vulnerable plugins and themes by checking your installation against CVE-2021-3754 and other known CVE records.

Scan My Site Free →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

Browse related advisories

All advisoriesCVE
✓