- 9.4CriticalCVSS base score
- 3.4%Exploitation in 30 daysEPSS · top 11% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- 1Public exploitsMetasploit, Nuclei and Exploit-DB
Description
ZEN Load Balancer versions 2.0 and 3.0-rc1 contain a command injection vulnerability in content2-2.cgi. The filelog parameter is passed directly into a backtick-delimited exec() call without sanitation. An authenticated attacker can inject arbitrary shell commands, resulting in remote code execution as the root user. ZEN Load Balancer is the predecessor of ZEVENET and SKUDONET. The affected versions (2.0 and 3.0-rc1) are no longer supported. SKUDONET CE is the current community-maintained successor.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. The public collections list a Metasploit module for it. 3 references of the record are tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits4
Metasploit modules1 module
- ZEN Load Balancer Filelog Command Execution (Metasploit module) (opens in a new tab)
exploit/linux/http/zen_load_balancer_execRank excellentdisclosed 14 Sept 2012
References tagged exploit3 references
- https://web.archive.org/web/20221203195056/https://itsecuritysolutions.org/2012-09-21-ZEN-Load-Balancer-v2.0-and-v3.0-rc1-multiple-vulnerabilities/ (opens in a new tab)technical-descriptionexploit
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/linux/http/zen_load_balancer_exec.rb (opens in a new tab)exploit
- https://www.exploit-db.com/exploits/21849 (opens in a new tab)exploit
Modules, templates and exploits as listed by the Metasploit Framework (BSD-3-Clause), ProjectDiscovery's Nuclei templates (MIT) and the Exploit Database (GPLv2), read once a day. Where the data comes from
Timeline
ID reserved
By VulnCheck
- 4 days later
· 4 days later
Published
- 8 months later
· 8 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulnCheckCNA (assigner) | 4.0 | Critical9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| NVDNVD · Deferred | 4.0 | Critical9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 3.4% · top 11% of all CVEs (9 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.4.
Affected products
ZEN Load Balancer · ZEN Load Balancer
- affected 2.0
- affected 3.0-rc1
References
5
- https://web.archive.org/web/20221203195056/https://itsecuritysolutions.org/2012-09-21-ZEN-Load-Balancer-v2.0-and-v3.0-rc1-multiple-vulnerabilities/ (opens in a new tab)technical-descriptionexploit
- https://web.archive.org/web/20111015031540/http://www.zenloadbalancer.com/ (opens in a new tab)product
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/linux/http/zen_load_balancer_exec.rb (opens in a new tab)exploit
- https://www.exploit-db.com/exploits/21849 (opens in a new tab)exploit
- https://www.fortiguard.com/encyclopedia/ips/33335/zen-load-balancer-filelog-command-execution (opens in a new tab)third-party-advisory
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2012-6599 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2012-10039)Record last updated .