What is CVE-2016-2056?

CVE-2016-2056 is a high-severity vulnerability in Xymon, classified under Command Injection. CVSS score: 8.8/10. Published 2016-04-13.

How severe is CVE-2016-2056?

High severity. CVSS v3 base score is 8.8 out of 10.

Is CVE-2016-2056 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

RCE in Xymon

CVE-2016-2056

xymond in Xymon 4.1.x, 4.2.x, and 4.3.x before 4.3.25 allow remote authenticated users to execute arbitrary commands via shell metacharacters in the adduser_name argument in (1) web/useradm.c or (2) web/chpasswd.c.

Vulnerability class: Command Injection (OS Command Injection)

Published 2016-04-13 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.545 (99.0th percentile), scored 2026-10-18.

High probability of exploitation in the next 30 days — patch promptly. 99th percentile — 99.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.545 · newest: 0.545 · change: 0.000

Affected products

Xymon — versions 4.1.0, 4.1.1, 4.1.2
Debian Linux — versions 8.0

Weakness classification (CWE)

CWE-77 — Command Injection

Public proof-of-concept exploits

rapid7/metasploit-framework

References

Frequently asked questions

What is CVE-2016-2056?: CVE-2016-2056 is a high-severity vulnerability in Xymon, classified under Command Injection. CVSS score: 8.8/10. Published 2016-04-13.
How severe is CVE-2016-2056?: High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2016-2056 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.