CVE intelligence and bounded remediation

CVE-2023-0871 — Opennms Horizon security vulnerability

Medium CVSS 6.1

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.

Severity
Medium
CVSS
6.1 (3.1)
Published
2023-08-11
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-611

Affected products

  • opennms / horizon
  • opennms / horizon / 31.0.8
  • opennms / meridian

Showing 3 representative product identities from 6 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

XML external entity and unsafe XML processing

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Check exposure

  • Inventory XML parsers used by APIs, file imports, office or image formats, identity protocols, feeds, and background jobs.
  • Determine whether document type declarations, external entities, XInclude, schemas, or network resolvers are enabled.
  • Map parser filesystem and network access and the sensitivity of documents it processes.

Remediate safely

  • Configure each parser to reject document type declarations and disable external entity, XInclude, and network resolution features.
  • Prefer a data format or hardened parser that does not support external resolution, and apply input size and depth limits.
  • Update affected XML libraries and centralize secure parser construction so callers cannot silently override it.

Authoritative sources

Complete CVE record and remediation plan

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