CVE-2026-40084: Cacti: Arbitrary File Read via Path Traversal in Report `format_file` Parameter

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-06-25 · updated 2026-06-29
Weakness: CWE-22

Description

Cacti is an open source performance and fault management framework. Versions 1.2.30 and prior are vulnerable to Path Traversal through the Report format_file Parameter, causing arbitrary file read. This vulnerability occurs in two stages. In the first stage (stored injection), lib/html_reports.php at line 283 stores $save['format_file'] = $post['format_file'] directly into the database without any validation. In the second stage (file read), lib/reports.php at line 667 concatenates CACTI_PATH_FORMATS . '/' . $format_file, and line 670 then calls file($format_file), reading arbitrary files from the filesystem. This issue has been fixed in version 1.2.31.

Affected products

cacti: before 1.2.31 — fixed in 1.2.31

How to fix

Upgrade to a fixed version: cacti 1.2.31. Check the vendor advisory for mitigations.

References

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