Cyber Resilience

CVE-2021-25933

MediumPublic PoC

Published: 20 May 2021

Published
20 May 2021
Modified
30 April 2025
KEV Added
Patch
CVSS Score v3.1 4.8 CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0049 66.0th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-25933 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Opennms Meridian. Its CVSS base score is 4.8 (Medium).

Operationally, ranked in the top 34.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation-2015.1.0-1 through meridian-foundation-2019.1.18-1; meridian-foundation-2020.1.0-1 through meridian-foundation-2020.1.6-1 are vulnerable to Stored Cross-Site Scripting, since the function `validateFormInput()` performs improper validation checks on the input sent to the `groupName` and `groupComment` parameters.…

more

Due to this flaw, an authenticated attacker could inject arbitrary script and trick other admin users into downloading malicious files which can cause severe damage to the organization using opennms.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

opennms
horizon
1.0 — 27.1.1
opennms
meridian
2015.1.0 — 2019.1.19 · 2020.1.0 — 2020.1.7

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References