How severe is CVE-2021-3513?

CVE-2021-3513 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-3513 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3513?

CVE-2021-3513 affects Redhat Keycloak. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3513?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-3513 published?

CVE-2021-3513 was published on 2022-08-22 and last updated on 2026-06-17.

CVE-2021-3513

CVE-2021-3513 is a high-severity vulnerability in Redhat Keycloak with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-209.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-209
Affected product: Redhat Keycloak
Published: 2022-08-22
Last modified: 2026-06-17

Description

A flaw was found in keycloak where a brute force attack is possible even when the permanent lockout feature is enabled. This is due to a wrong error message displayed when wrong credentials are entered. The highest threat from this vulnerability is to confidentiality.

Frequently asked questions

What is CVE-2021-3513?: A flaw was found in keycloak where a brute force attack is possible even when the permanent lockout feature is enabled. This is due to a wrong error message displayed when wrong credentials are entered. The highest threat from this vulnerability is to confidentiality.
How severe is CVE-2021-3513?: CVE-2021-3513 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-3513 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3513?: CVE-2021-3513 affects Redhat Keycloak. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3513?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-3513 published?: CVE-2021-3513 was published on 2022-08-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:redhat:keycloak:*:*:*:*:*:*:*:*

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