How severe is CVE-2021-3597?

CVE-2021-3597 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-3597 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3597?

CVE-2021-3597 primarily affects Redhat Fuse. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3597?

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

When was CVE-2021-3597 published?

CVE-2021-3597 was published on 2022-05-24 and last updated on 2026-06-17.

CVE-2021-3597

CVE-2021-3597 is a medium-severity vulnerability in Redhat Fuse with a CVSS 3.x base score of 5.9. 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-362.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 2.6
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-362
Affected product: Redhat Fuse
Published: 2022-05-24
Last modified: 2026-06-17

Description

A flaw was found in undertow. The HTTP2SourceChannel fails to write the final frame under some circumstances, resulting in a denial of service. The highest threat from this vulnerability is availability. This flaw affects Undertow versions prior to 2.0.35.SP1, prior to 2.2.6.SP1, prior to 2.2.7.SP1, prior to 2.0.36.SP1, prior to 2.2.9.Final and prior to 2.0.39.Final.

Frequently asked questions

What is CVE-2021-3597?: A flaw was found in undertow. The HTTP2SourceChannel fails to write the final frame under some circumstances, resulting in a denial of service. The highest threat from this vulnerability is availability. This flaw affects Undertow versions prior to 2.0.35.SP1, prior to 2.2.6.SP1, prior to 2.2.7.SP1, prior to 2.0.36.SP1, prior to 2.2.9.Final and prior to 2.0.39.Final.
How severe is CVE-2021-3597?: CVE-2021-3597 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-3597 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3597?: CVE-2021-3597 primarily affects Redhat Fuse. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3597?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3597 published?: CVE-2021-3597 was published on 2022-05-24 and last updated on 2026-06-17.

References

Affected products (18)

cpe:2.3:a:redhat:fuse:1.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:-:*:*:*:text-only:*:*:*
cpe:2.3:a:redhat:openshift_application_runtimes:-:*:*:*:text-only:*:*:*
cpe:2.3:a:redhat:single_sign-on:-:*:*:*:text-only:*:*:*
cpe:2.3:a:redhat:undertow:*:*:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:2.0.35:-:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:2.0.36:-:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:2.0.39:-:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:2.2.6:-:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:2.2.7:-:*:*:*:*:*:*
cpe:2.3:a:redhat:undertow:2.2.9:-:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.3:*:*:*:*:*:*:*
cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.4:*:*:*:*:*:*:*
cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:linux:*:*
cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:windows:*:*
cpe:2.3:a:netapp:oncommand_insight:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:oncommand_workflow_automation:-:*:*:*:*:*:*:*

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Other CWE-362 (Race Condition) vulnerabilities

CVE-2022-27626 — Critical (CVSS 10.0): A vulnerability regarding concurrent execution using shared resource with improper synchronization ('Race Condition')…
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CVE-2010-1228 — Critical (CVSS 10.0): Multiple race conditions in the sandbox infrastructure in Google Chrome before 4.1.249.1036 have unspecified impact and…
CVE-2008-6598 — Critical (CVSS 10.0): Multiple race conditions in WANPIPE before 3.3.6 have unknown impact and attack vectors related to "bri restart logic."
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