UndertowApplication · Redhat
CVE-2020-1745
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 · uneditedA file inclusion vulnerability was found in the AJP connector enabled with a default AJP configuration port of 8009 in Undertow version 2.0.29.Final and before and was fixed in 2.0.30.Final. A remote, unauthenticated attacker could exploit this vulnerability to read web application files from a vulnerable server. In instances where the vulnerable server allows file uploads, an attacker could upload malicious JavaServer Pages (JSP) code within a variety of file types and trigger this vulnerability to gain remote code execution.
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 · high confidenceA file inclusion vulnerability exists in Undertow's AJP connector (default port 8009) for versions 2.0.29.Final and prior. An unauthenticated remote attacker can exploit this to read web application files, and if file uploads are permitted, can upload malicious JSP code to achieve remote code execution.
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
UndertowApplication
<= 2.0.29CVSS 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
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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 checksWork through these to decide whether this CVE applies to you.
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Identify Undertow versionLocate the undertow-core JAR file in your deployment or check your dependency management system (Maven pom.xml, Gradle build file) for the undertow-core version entryAffected if The version is 2.0.29.Final or earlier
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Confirm AJP connector is enabledReview your server configuration files for any AJP connector definition listening on port 8009, or run 'netstat -an | grep 8009' or 'ss -tlnp | grep 8009' to check if port 8009 is open and listeningAffected if Port 8009 is open and an AJP connector is configured
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Check if file uploads are permittedExamine your web application's deployment descriptor (web.xml) or application configuration for file upload handling (multipart-config, org.apache.tomcat.util.http.fileupload, or similar servlet 3.0+ file upload configuration)Affected if File upload functionality is enabled in the web application
Your environment is vulnerable if Undertow version is 2.0.29.Final or earlier AND the AJP connector on port 8009 is enabled and accessible
Generated from the published advisory. Verify against your own configuration.
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 · scopedUpgrade Undertow to version 2.0.30.Final or later. If immediate upgrade is not feasible, disable or restrict access to the AJP connector on port 8009 until the patch can be applied.
2.0.30.Final or later
- Upgrade Undertow to version 2.0.30.Final or later to remediate the AJP connector file inclusion vulnerability
- If Undertow is embedded within WildFly or JBoss EAP, upgrade the respective application server to a version that includes Undertow 2.0.30.Final or newer
- After upgrading, verify that the AJP connector configuration is still functioning correctly for any reverse proxy setups
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Undertow
Scoped from the published advisory
- Consultation3.0 h
- Implementation4.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,128.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-1745 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2020-1745 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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