CVE-2023-34054
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 · uneditedIn Reactor Netty HTTP Server, versions 1.1.x prior to 1.1.13 and versions 1.0.x prior to 1.0.39, it is possible for a user to provide specially crafted HTTP requests that may cause a denial-of-service (DoS) condition. Specifically, an application is vulnerable if Reactor Netty HTTP Server built-in integration with Micrometer is enabled.
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 confidenceReactor Netty HTTP Server versions prior to 1.1.13 and 1.0.39 contain a denial-of-service vulnerability where specially crafted HTTP requests can cause the server to become unresponsive. The vulnerability is only present when the built-in integration with Micrometer (metrics collection) is enabled.
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< 1.0.39>= 1.1.0, < 1.1.13CVSS 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
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 Reactor Netty as a dependencyReview your project's dependency manifest (Maven pom.xml, Gradle build.gradle, or the lib/ directory) for reactor-netty-core, reactor-netty-http, or reactor-netty-http-client artifacts.Affected if Reactor Netty is present in the runtime dependencies
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Determine the installed Reactor Netty versionLocate the reactor-netty-http JAR file and inspect its MANIFEST.MF or version file, or query your build tool for the resolved version (e.g., mvn dependency:tree or gradle dependencies). Compare the version number against the affected ranges: < 1.0.39, or >= 1.1.0 and < 1.1.13.Affected if The installed version falls within < 1.0.39 or >= 1.1.0, < 1.1.13
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Check if Micrometer metrics integration is enabledInspect your application configuration files (application.yml, application.properties) or programmatic initialization code for Micrometer/metrics settings. Look for properties such as management.metrics.enable, reactor.netty.metrics.enabled, or the presence of micrometer-registry-* dependencies along with explicit metrics configuration.Affected if Micrometer metrics collection is explicitly enabled or auto-configuration has enabled it; the vulnerability does not apply when metrics are disabled
You are affected only if your environment uses Reactor Netty in an affected version AND has Micrometer metrics collection enabled.
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 · scoped1.0.391.1.13
Upgrade Reactor Netty to version 1.1.13+ or 1.0.39+ to resolve this vulnerability, or disable the Micrometer integration if metrics are not required.
Reactor Netty 1.0.39 or 1.1.13 (or later)
- 1. Identify your current Reactor Netty version by checking your dependency management (Maven pom.xml, Gradle build.gradle, or your lock files)
- 2. If using Reactor Netty 1.0.x, upgrade to version 1.0.39 or later
- 3. If using Reactor Netty 1.1.x, upgrade to version 1.1.13 or later
- 4. If using an older version (< 1.0.x), upgrade directly to 1.0.39 or 1.1.13
- 5. Rebuild and redeploy your application
- 6. Verify the application starts successfully and test HTTP endpoints
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation2.0 h
- Testing4.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-34054 — 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-2023-34054 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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