CVE-2026-65639
OS command injection in the advanced-rule parser of ConfigServer Security & Firewall allows a remote attacker who controls a configured allow/deny feed to execute arbitrary commands as root, due to insufficient validation of feed-supplied rule data. The vulnerability affects versions of the software originally distributed by ConfigServer, as well as versions of the WebPros-maintained fork that contain the vulnerable code. WebPros has addressed the vulnerability in version 16.30. Other forks or independently maintained versions of ConfigServer Security & Firewall (CSF) may also be affected and should be evaluated independently.
What this means for your business
- FIRST's prediction model gives it a 2% chance of attack attempts being seen in the next 30 days, ranking above 74% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Fastnexa security experts
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 9.5
- Weakness
- CWE-78
- Assigned by
- support@hackerone.com
Dates
- Published
- 2026-09-10
- Last modified
- 2026-09-10
- Sources
- NVD