Vulnerability Description
Cacti is an open source performance and fault management framework. Versions 1.2.30 and prior are vulnerable to Open Redirect through a substring check rather than a host check at str_contains($referer, CACTI_PATH_URL). When the user's login_opts == '1' (redirect to referer after login), the function used $_SERVER['HTTP_REFERER'] directly. An attacker could craft a referer such as https://evil.com/cacti/. Where CACTI_PATH_URL is /cacti/, the substring matches and the user is redirected to evil.com after login. The pre-existing validate_redirect_url() helper at lib/html_utility.php performed proper validation but was not invoked from auth_login_redirect(). This issue has been fixed in version 1.2.31.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/Cacti/cacti/releases/tag/release%2F1.2.31
- https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq
- https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq
FAQ
What is CVE-2026-40080?
CVE-2026-40080 is a vulnerability with a CVSS score of 6.1 (MEDIUM). Cacti is an open source performance and fault management framework. Versions 1.2.30 and prior are vulnerable to Open Redirect through a substring check rather than a host check at str_contains($refere...
How severe is CVE-2026-40080?
CVE-2026-40080 has been rated MEDIUM with a CVSS base score of 6.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-40080?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.