How severe is CVE-2021-3642?

CVE-2021-3642 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-3642 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3642?

CVE-2021-3642 primarily affects Redhat Wildfly Elytron. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3642?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-3642 published?

CVE-2021-3642 was published on 2021-08-05 and last updated on 2026-06-17.

CVE-2021-3642

CVE-2021-3642 is a medium-severity vulnerability in Redhat Wildfly Elytron with a CVSS 3.x base score of 5.3. 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 3.5
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Redhat Wildfly Elytron
Published: 2021-08-05
Last modified: 2026-06-17

Description

A flaw was found in Wildfly Elytron in versions prior to 1.10.14.Final, prior to 1.15.5.Final and prior to 1.16.1.Final where ScramServer may be susceptible to Timing Attack if enabled. The highest threat of this vulnerability is confidentiality.

Frequently asked questions

What is CVE-2021-3642?: A flaw was found in Wildfly Elytron in versions prior to 1.10.14.Final, prior to 1.15.5.Final and prior to 1.16.1.Final where ScramServer may be susceptible to Timing Attack if enabled. The highest threat of this vulnerability is confidentiality.
How severe is CVE-2021-3642?: CVE-2021-3642 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-3642 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3642?: CVE-2021-3642 primarily affects Redhat Wildfly Elytron. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3642?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3642 published?: CVE-2021-3642 was published on 2021-08-05 and last updated on 2026-06-17.

References

https://bugzilla.redhat.com/show_bug.cgi?id=1981407

Affected products (13)

cpe:2.3:a:redhat:wildfly_elytron:*:*:*:*:*:*:*:*
cpe:2.3:a:redhat:build_of_quarkus:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:codeready_studio:12.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:data_grid:8.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:descision_manager:7.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:integration_camel_k:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:integration_camel_quarkus:*:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.0.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform_expansion_pack:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_fuse:7.0.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openshift_application_runtimes:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:process_automation:7.0:*:*:*:*:*:*:*
cpe:2.3:a:quarkus:quarkus:*:*:*:*:*:*:*:*

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