CVE-2026-40080
Cacti: Open Redirect via HTTP_REFERER substring check in auth_login_redirect
- State
- Published
- Severity
- 6.1 Medium
- Published
- Jun 25, 2026
- Updated
- Jun 26, 2026
- Reserved
- Apr 9, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 6.1 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N | GitHub_M |
Weaknesses
- CWE-601 URL Redirection to Untrusted Site ('Open Redirect')
Affected Products
| Product | Versions |
|---|---|
cactiCacti |
|
References
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