CVE-2021-3629

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-05-24 · updated 2026-06-17
Weakness: CWE-400

Description

A flaw was found in Undertow. A potential security issue in flow control handling by the browser over http/2 may potentially cause overhead or a denial of service in the server. The highest threat from this vulnerability is availability. This flaw affects Undertow versions prior to 2.0.40.Final and prior to 2.2.11.Final.

Affected products

Active IQ Unified Manager for VMware vSphere, Linux, and Microsoft Windows: all versions
OnCommand Insight: all versions
NetApp OnCommand Workflow Automation: all versions
RedHat Integration: all versions
Red Hat JBoss EAP: 7.4, 7.3
Red Hat Single Sign-On: all versions
Red Hat undertow: before 2.0.40; from 2.2.0 before 2.2.11 — fixed in 2.0.40, 2.2.11
RedHat Wildfly Core: before 17.0 — fixed in 17.0

How to fix

Upgrade to a fixed version: Red Hat undertow 2.0.40, 2.2.11; RedHat Wildfly Core 17.0. Check the vendor advisory for mitigations.

References

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