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 strcontains($referer, CACTIPATHURL). When the user's loginopts == '1' (redirect to referer after login), the function used $SERVER['HTTPREFERER'] directly. An attacker could craft a referer such as https://evil.com/cacti/. Where CACTIPATHURL is /cacti/, the substring matches and the user is redirected to evil.com after login. The pre-existing validateredirecturl() helper at lib/htmlutility.php performed proper validation but was not invoked from authlogin_redirect(). This issue has been fixed in version 1.2.31.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40080.json",
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-601"
]
}{
"cpe": "cpe:2.3:a:cacti:cacti:*:*:*:*:*:*:*:*",
"source": [
"AFFECTED_FIELD",
"CPE_RANGE"
],
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "1.2.31"
}
]
}