CVE-2016-2056
Status: ModifiedHigh (8.8)—Exploit
Severity8.8High · CVSS 3.0
Exploitation probability55 %higher than 99% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitAvailablePublished on Exploit-DB · Metasploit module (reliable, widely available exploit)
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.
CVSS
- Base score
- 8.8
- Version
- 3.0
- Vector
- CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days
- 55 %
- Percentile among all scored CVEs
- 99
- Score date
- 10/21/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Public exploits
Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.
- Metasploit module (reliable, widely available exploit) · Xymon useradm Command Execution
- Published on Exploit-DB · Xymon 4.3.25 - useradm Command Execution (Metasploit) (7/12/2019)
Affected technologies (2)
CWEs
- CWE-77
References
Show 10 references
- http://packetstormsecurity.com/files/135758/Xymon-4.3.x-Buffer-Overflow-Code-Execution-Information-Disclosure.html
- http://packetstormsecurity.com/files/153620/Xymon-useradm-Command-Execution.html
- http://www.debian.org/security/2016/dsa-3495
- http://www.securityfocus.com/archive/1/537522/100/0/threaded
- https://sourceforge.net/p/xymon/code/7892/
- http://packetstormsecurity.com/files/135758/Xymon-4.3.x-Buffer-Overflow-Code-Execution-Information-Disclosure.html
- http://packetstormsecurity.com/files/153620/Xymon-useradm-Command-Execution.html
- http://www.debian.org/security/2016/dsa-3495
- http://www.securityfocus.com/archive/1/537522/100/0/threaded
- https://sourceforge.net/p/xymon/code/7892/
Raw JSON (NVD)
Show
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