dbcve.org
Build Of Apache Camel HawtioWeb server / proxy · Redhat

CVE-2026-28367

CRITICAL · 9.1 CVSS v3.1 Published 2026-03-27
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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. A remote attacker can exploit this vulnerability by sending `\r\r\r` as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic Application Load Balancer, potentially leading to unauthorized access or manipulation of web requests.

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 · moderate confidence

Undertow HTTP server improperly accepts the non-standard header block terminator `\r\r\r` (instead of the RFC-compliant `\r\n\r\n`). This parsing inconsistency enables HTTP request smuggling attacks when Undertow sits behind legacy proxies like older Apache Traffic Server or Google Cloud Classic Application Load Balancer that do not recognize this alternate terminator, allowing attackers to bypass proxy controls and inject or manipulate backend requests.

MitigationUpgrade Undertow to the patched version that properly rejects non-standard header terminators. Additionally, ensure proxy servers are updated to modern versions and consider enforcing HTTP/2 or TLS to mitigate request smuggling vectors.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

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
Build Of Apache Camel HawtioWeb server / proxy
Affected:= 4.0
Build Of Apache Camel For Spring BootWeb server / proxy
Affected:= 4.0
Data GridApplication
Affected:= 8.0
FuseApplication
Affected:= 7.0.0
Jboss Enterprise Application PlatformApplication
Affected:= 7.0.0= 8.0.0
Jboss Enterprise Application Platform Expansion PackApplication
Affected:all versions
Process AutomationApplication
Affected:= 7.0
Single Sign OnApplication
Affected:= 7.0

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
High
Integrity
High
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the Undertow version in use
    Check the undertow-core library version packaged with your application or check the version reported by the JBoss/WildFly server (for JBoss EAP, use /core-service=server:read-attribute(name=undertow-version) in jboss-cli or check the server log at startup)
    Affected if The installed Undertow version falls within the vulnerable range for your specific Red Hat product and matches the affected versions listed (EAP 7.0.0, 8.0.0; Fuse 7.0.0; Data Grid 8.0; etc.)
  2. Confirm the application runs behind a reverse proxy or load balancer
    Review your infrastructure architecture to determine if Undertow sits behind a proxy such as Apache Traffic Server, Google Cloud Classic Application Load Balancer, or other HTTP proxy/gateway
    Affected if Undertow is directly exposed to clients without an intervening proxy, the smuggling vector does not apply in the typical attack scenario described
  3. Identify the proxy type and version
    Check the proxy configuration and version - for Apache Traffic Server look at the installed version (ats version or package info); for Google Cloud check the Classic Application Load Balancer type in the Cloud Console; for other proxies review their version documentation
    Affected if The proxy is a legacy version that does not recognize the non-standard \r\r\r header terminator and fails to normalize requests before forwarding to Undertow
  4. Test for header terminator handling
    Send a crafted HTTP request with \r\r\r (non-standard) instead of \r\n\r\n as the header block terminator to your endpoint and observe whether Undertow processes it differently than \r\n\r\n
    Affected if Undertow accepts and processes requests with \r\r\r as a valid header terminator, indicating the parsing inconsistency is present

You are affected if your Red Hat product uses a vulnerable Undertow version AND the server is positioned behind a legacy proxy that does not normalize non-standard header terminators, allowing HTTP request smuggling to occur.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade Undertow to the patched version that properly rejects non-standard header terminators. Additionally, ensure proxy servers are updated to modern versions and consider enforcing HTTP/2 or TLS to mitigate request smuggling vectors.

Recommended fix Moderate confidence

Undertow 2.3.17+ or latest stable 2.x/3.x release; For JBoss EAP, apply latest Red Hat errata for affected versions

  1. Identify the Undertow version in use by checking project dependencies (Maven pom.xml, Gradle build.gradle, or container image)
  2. For JBoss Enterprise Application Platform: Upgrade to the latest available patch for versions 7.0.0, 7.0.1, 7.0.2, 7.1.0, 7.2.0, 7.3.0, 7.4.0, or 8.0.0 as provided by Red Hat through errata updates
  3. For Red Hat Fuse: Apply the relevant security update for version 7.0.0
  4. For Red Hat Data Grid: Apply the security update for version 8.0
  5. For Red Hat Process Automation and Single Sign On: Apply updates for version 7.0
  6. If direct Undertow upgrade is possible, upgrade to Undertow 2.3.17 or later (or latest stable 2.x/3.x)
  7. Verify the fix by testing with HTTP requests containing \r\r\r sequences to ensure they are properly rejected
  8. Review proxy configurations to ensure they properly handle HTTP header parsing to prevent smuggling
Caveat May require application testing if there are legitimate uses of non-standard line endings in headers; review proxy chain compatibility after upgrade

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

Fix this in Build Of Apache Camel Hawtio Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-28367 — 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-2026-28367 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