CVE-2016-2056

Exp

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.

Published: 2016-04-13 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-2056 is rated High Exploit Risk (80.6/100): CVSS High severity, with high exploitation likelihood (EPSS 56.35%, 98th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2016-2056

EDB-ID Source Kind Published Link
47114 exploit_db edb 2019-07-12 Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2016-2056

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-09-14 60.26% 56.35% -3.91%
2 2025-07-25 66.02% 60.26% -5.76%
3 2025-03-30 — 66.02% —

Full EPSS history (21 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-2056

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.0 6.4 [email protected]

Weakness enumeration for CVE-2016-2056

OS Trackers for CVE-2016-2056

vendor priority summary link
debian not yet assigned CVE-2016-2056 not yet assigned priority: Debian including 1 source packages (xymon), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-2056
ubuntu medium CVE-2016-2056 medium priority: Ubuntu including 1 source packages (xymon), 11 status rows across 11 suites (artful, bionic, cosmic, disco, precise, trusty, upstream, wily, xenial, yakkety, zesty): not-affected 7, ignored 2, DNE 1, released 1. https://ubuntu.com/security/CVE-2016-2056

Affected software / configurations for CVE-2016-2056

Vendor Product Version Raw CPE
xymon xymon 4.1.0 cpe:2.3:a:xymon:xymon:4.1.0:*:*:*:*:*:*:*
xymon xymon 4.1.1 cpe:2.3:a:xymon:xymon:4.1.1:*:*:*:*:*:*:*
xymon xymon 4.1.2 cpe:2.3:a:xymon:xymon:4.1.2:*:*:*:*:*:*:*
xymon xymon 4.1.2 cpe:2.3:a:xymon:xymon:4.1.2:p1:*:*:*:*:*:*
xymon xymon 4.1.2 cpe:2.3:a:xymon:xymon:4.1.2:p2:*:*:*:*:*:*
xymon xymon 4.2 cpe:2.3:a:xymon:xymon:4.2:alfa:*:*:*:*:*:*
xymon xymon 4.2 cpe:2.3:a:xymon:xymon:4.2:beta20060605:*:*:*:*:*:*
xymon xymon 4.2 cpe:2.3:a:xymon:xymon:4.2:rc20060712:*:*:*:*:*:*
xymon xymon 4.2.0 cpe:2.3:a:xymon:xymon:4.2.0:*:*:*:*:*:*:*
xymon xymon 4.2.2 cpe:2.3:a:xymon:xymon:4.2.2:*:*:*:*:*:*:*
xymon xymon 4.2.2 cpe:2.3:a:xymon:xymon:4.2.2:rc1:*:*:*:*:*:*
xymon xymon 4.2.3 cpe:2.3:a:xymon:xymon:4.2.3:*:*:*:*:*:*:*
xymon xymon 4.2.3 cpe:2.3:a:xymon:xymon:4.2.3:rc1:*:*:*:*:*:*
xymon xymon 4.3.0 cpe:2.3:a:xymon:xymon:4.3.0:*:*:*:*:*:*:*
xymon xymon 4.3.0 cpe:2.3:a:xymon:xymon:4.3.0:beta1:*:*:*:*:*:*
xymon xymon 4.3.0 cpe:2.3:a:xymon:xymon:4.3.0:beta2:*:*:*:*:*:*
xymon xymon 4.3.0 cpe:2.3:a:xymon:xymon:4.3.0:beta3:*:*:*:*:*:*
xymon xymon 4.3.0 cpe:2.3:a:xymon:xymon:4.3.0:rc1:*:*:*:*:*:*
xymon xymon 4.3.1 cpe:2.3:a:xymon:xymon:4.3.1:*:*:*:*:*:*:*
xymon xymon 4.3.2 cpe:2.3:a:xymon:xymon:4.3.2:*:*:*:*:*:*:*
xymon xymon 4.3.3 cpe:2.3:a:xymon:xymon:4.3.3:*:*:*:*:*:*:*
xymon xymon 4.3.4 cpe:2.3:a:xymon:xymon:4.3.4:*:*:*:*:*:*:*
xymon xymon 4.3.5 cpe:2.3:a:xymon:xymon:4.3.5:*:*:*:*:*:*:*
xymon xymon 4.3.6 cpe:2.3:a:xymon:xymon:4.3.6:*:*:*:*:*:*:*
xymon xymon 4.3.7 cpe:2.3:a:xymon:xymon:4.3.7:*:*:*:*:*:*:*
xymon xymon 4.3.8 cpe:2.3:a:xymon:xymon:4.3.8:*:*:*:*:*:*:*
xymon xymon 4.3.9 cpe:2.3:a:xymon:xymon:4.3.9:*:*:*:*:*:*:*
xymon xymon 4.3.10 cpe:2.3:a:xymon:xymon:4.3.10:*:*:*:*:*:*:*
xymon xymon 4.3.11 cpe:2.3:a:xymon:xymon:4.3.11:*:*:*:*:*:*:*
xymon xymon 4.3.12 cpe:2.3:a:xymon:xymon:4.3.12:*:*:*:*:*:*:*
xymon xymon 4.3.13 cpe:2.3:a:xymon:xymon:4.3.13:*:*:*:*:*:*:*
xymon xymon 4.3.14 cpe:2.3:a:xymon:xymon:4.3.14:*:*:*:*:*:*:*
xymon xymon 4.3.15 cpe:2.3:a:xymon:xymon:4.3.15:*:*:*:*:*:*:*
xymon xymon 4.3.16 cpe:2.3:a:xymon:xymon:4.3.16:*:*:*:*:*:*:*
xymon xymon 4.3.17 cpe:2.3:a:xymon:xymon:4.3.17:*:*:*:*:*:*:*
xymon xymon 4.3.18 cpe:2.3:a:xymon:xymon:4.3.18:*:*:*:*:*:*:*
xymon xymon 4.3.19 cpe:2.3:a:xymon:xymon:4.3.19:*:*:*:*:*:*:*
xymon xymon 4.3.19 cpe:2.3:a:xymon:xymon:4.3.19:rc1:*:*:*:*:*:*
xymon xymon 4.3.20 cpe:2.3:a:xymon:xymon:4.3.20:*:*:*:*:*:*:*
xymon xymon 4.3.21 cpe:2.3:a:xymon:xymon:4.3.21:*:*:*:*:*:*:*
xymon xymon 4.3.22 cpe:2.3:a:xymon:xymon:4.3.22:*:*:*:*:*:*:*
xymon xymon 4.3.23 cpe:2.3:a:xymon:xymon:4.3.23:*:*:*:*:*:*:*
xymon xymon 4.3.24 cpe:2.3:a:xymon:xymon:4.3.24:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

References for CVE-2016-2056

cvelogic Threat Intelligence