CVE-2026-127236: Argument Injection Vulnerability Exists
Source GCVE Database
Not known to be exploited · CVSS 5.4 Medium · fixed in 2026.0.2 : update Meridian when convenient.
Data as of 12 Nov 2026, 22:33 UTC
Thin evidence
One scorer or none| CNA (OpenNMS) | CVSS 3.1 | 5.4 |
|---|
- Patch
- Available – fixed in 2026.0.2, 2025.0.12, 2024.3.15 +1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 12 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 12 Nov 2026.
What to do
Upgrade Meridian to 2026.0.2, 2025.0.12 or 2024.3.15; Horizon to 36.0.6.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| The OpenNMS GroupMeridian | Affected
| Fixed in
|
| The OpenNMS GroupMeridian | Affected
| Fixed in
|
| The OpenNMS GroupMeridian | Affected
| Fixed in
|
| The OpenNMS GroupHorizon | Affected
| Fixed in
|
GitHubMeridianpkg:github/MeridianOther threats | Affected
| Fixed in
|
GitHubHorizonpkg:github/HorizonOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to OpenNMS Meridian versions 2024.3.15, 2025.0.12, 2026.0.2 or Horizon 36.0.6 or newer, which include validation of ad-hoc graph parameters against allowlists. Follow vendor guidance to restrict installation to private networks and avoid direct Internet exposure. No additional mitigation is required if these versions are deployed.
Description
An argument injection vulnerability in the ad-hoc RRD graph feature of OpenNMS Meridian and Horizon allows low-privileged authenticated users to inject extra rrdtool arguments. This can lead to server-side request forgery and unauthorized local file reads. The vulnerability does not allow arbitrary OS command execution due to the use of exec with argument arrays and no shell. Fixed versions are available that validate input parameters against allowlists.