CVE-2023-0871
An XML External Entity injection vulnerability
XXE injection in /rtc/post/ endpoint in OpenMNS 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. OpenNMS thanks Erik Wynter and Moshe Apelbaum for reporting this issue.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
5.4
An XML External Entity injection vulnerability
XXE injection in /rtc/post/ endpoint in OpenMNS 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. OpenNMS thanks Erik Wynter and Moshe Apelbaum for reporting this issue.
- Record
CVE-2023-0871- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:L - Weakness
- CWE-611
- Updated
- 2026-11-02
EUVDEUVD-2023-2186
5.4
XXE injection in /rtc/post/ endpoint in OpenMNS 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. OpenNMS thanks Erik Wynter and Moshe Apelbaum for reporting this issue.
- Record
EUVD-2023-2186- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:L - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-2qc8-r663-v864
8.8
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.
- Record
GHSA-2qc8-r663-v864- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:L - Weakness
- CWE-611
- Updated
- 2026-11-02
NVD
5.4
XXE injection in /rtc/post/ endpoint in OpenMNS 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. OpenNMS thanks Erik Wynter and Moshe Apelbaum for reporting this issue.
- Record
CVE-2023-0871- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:L - CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-611
- Updated
- 2026-11-02
OSV
5.4
An XML External Entity injection vulnerability
XXE injection in /rtc/post/ endpoint in OpenMNS 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. OpenNMS thanks Erik Wynter and Moshe Apelbaum for reporting this issue.
- Record
CVE-2023-0871- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:L - Weakness
- CWE-611
- Updated
- 2026-11-02
OSVGHSA-2qc8-r663-v864
8.8
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.
- Record
GHSA-2qc8-r663-v864- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:L - Weakness
- CWE-611
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
org.opennms.core:org.opennms.core.xmlMaven |
31.0.8 up to 32.0.2 | 32.0.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-0871 is a medium vulnerability (CVSS 5.4) in Opennms Horizon, published August 11, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.55%, the 46th percentile. Fixed in org.opennms.core:org.opennms.core.xml 32.0.2.
References
github.com/OpenNMS/opennms/pull/6355
docs.opennms.com/horizon/32/releasenotes/changelog.html
nvd.nist.gov/vuln/detail/CVE-2023-0871
github.com/OpenNMS/opennms/commit/5a3b0b62e0c612c9e2aa2c91c847abec71d767d5
github.com/advisories/GHSA-2qc8-r663-v864
github.com/CVEProject/cvelistV5/tree/main/cves/2023/0xxx/CVE-2023-0871.json
github.com/OpenNMS/opennms