dbcve.org
Jboss Enterprise Application PlatformApplication · Redhat

CVE-2021-3859

HIGH · 7.5 CVSS v3.1 Published 2022-08-26
Fix available
A fix is available. Upgrade to 2.2.15 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A flaw was found in Undertow that tripped the client-side invocation timeout with certain calls made over HTTP2. This flaw allows an attacker to carry out denial of service attacks.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Jboss Enterprise Application PlatformApplication
Affected:= 7.3= 7.4
Single Sign OnApplication
Affected:= 7.4.10= 7.5.1
UndertowApplication
Affected:< 2.2.15
Cloud Secure AgentApplication
Affected:all versions
Oncommand InsightApplication
Affected:all versions
Oncommand Workflow AutomationApplication
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2.2.15 or later
Fixed in 2.2.15
Vendor patch github.com →
Recommended fix High confidence

Undertow 2.2.15 or later; JBoss EAP 7.3/7.4 with latest cumulative patch; RH-SSO 7.4.11 or 7.5.2

  1. Identify the Undertow version currently in use by checking project dependencies or JAR manifests
  2. Upgrade Undertow dependency to version 2.2.15 or later in your build configuration (Maven pom.xml, Gradle build.gradle, or container base image)
  3. If using JBoss EAP, apply the appropriate cumulative patch (CP) for versions 7.3 or 7.4 that addresses this vulnerability
  4. For Red Hat Single Sign-On, upgrade to version 7.4.11+ or 7.5.2+ respectively
  5. Rebuild and redeploy the application
  6. Verify the fix by testing HTTP/2 client invocations to ensure timeouts no longer occur erroneously
Caveat Upgrading Undertow may introduce behavioral changes in HTTP/2 handling; test thoroughly before production deployment

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,950. Get the upgrade done

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-3859 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-3859 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data