What is CVE-2023-0871?

CVE-2023-0871 is a high-severity XML external entity injection (XXE) vulnerability in org.opennms.core:org.opennms.core.xml (maven), affecting versions >= 31.0.8, < 32.0.2. It is fixed in 32.0.2. An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs.

How severe is CVE-2023-0871?

CVE-2023-0871 has a CVSS score of 8.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which versions of org.opennms.core:org.opennms.core.xml are affected by CVE-2023-0871?

org.opennms.core:org.opennms.core.xml (maven) versions >= 31.0.8, < 32.0.2 is affected.

Is there a fix for CVE-2023-0871?

Yes. CVE-2023-0871 is fixed in 32.0.2. Upgrade to this version or later.

Is CVE-2023-0871 exploitable, and should I be worried?

Whether CVE-2023-0871 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2023-0871 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2023-0871

Q: How severe is CVE-2023-0871?

CVE-2023-0871 has a CVSS score of 8.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Q: Which versions of org.opennms.core:org.opennms.core.xml are affected by CVE-2023-0871?

org.opennms.core:org.opennms.core.xml (maven) versions >= 31.0.8, < 32.0.2 is affected.

Q: Is there a fix for CVE-2023-0871?

Yes. CVE-2023-0871 is fixed in 32.0.2. Upgrade to this version or later.

Q: Is CVE-2023-0871 exploitable, and should I be worried?

Whether CVE-2023-0871 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2023-0871 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2023-0871?

Upgrade org.opennms.core:org.opennms.core.xml to 32.0.2 or later.

Summary

OpenNMS Horizon XXE Injection Vulnerability

XXE injection in /rtc/post/ endpoint in OpenNMS Horizon 31.0.8 and versions earlier than 32.0.2 on multiple platforms is vulnerable to XML external entity (XXE) injection, which can be used for instance to force Horizon to make arbitrary HTTP requests to internal and external services. The solution is to upgrade to Meridian 2023.1.6, 2022.1.19, 2021.1.30, 2020.1.38 or Horizon 32.0.2 or newer. Meridian and Horizon installation instructions state that they are intended for installation within an organization's private networks and should not be directly accessible from the Internet.

Impact

An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs. Typical impact: local file disclosure, server-side request forgery, or denial of service.

CVE-2023-0871 has a CVSS score of 8.8 (High). The vector is reachable from an adjacent network, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (32.0.2); upgrading removes the vulnerable code path.

Affected versions

org.opennms.core:org.opennms.core.xml (>= 31.0.8, < 32.0.2)

Security releases

org.opennms.core:org.opennms.core.xml → 32.0.2 (maven)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade org.opennms.core:org.opennms.core.xml to 32.0.2 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2023-0871? CVE-2023-0871 is a high-severity XML external entity injection (XXE) vulnerability in org.opennms.core:org.opennms.core.xml (maven), affecting versions >= 31.0.8, < 32.0.2. It is fixed in 32.0.2. An XML parser processes external entity references in untrusted input, causing the server to fetch internal resources or remote URLs.
How severe is CVE-2023-0871? CVE-2023-0871 has a CVSS score of 8.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which versions of org.opennms.core:org.opennms.core.xml are affected by CVE-2023-0871? org.opennms.core:org.opennms.core.xml (maven) versions >= 31.0.8, < 32.0.2 is affected.
Is there a fix for CVE-2023-0871? Yes. CVE-2023-0871 is fixed in 32.0.2. Upgrade to this version or later.
Is CVE-2023-0871 exploitable, and should I be worried? Whether CVE-2023-0871 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2023-0871 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2023-0871? Upgrade org.opennms.core:org.opennms.core.xml to 32.0.2 or later.