CVE-2026-40080
Cacti: Open Redirect via HTTP_REFERER substring check in auth_login_redirect
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.
INFO
Published Date :
June 25, 2026, 11:17 p.m.
Last Modified :
June 29, 2026, 6:52 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update Cacti to version 1.2.31 or later.
- Apply vendor patches when available.
- Review input validation for redirect URLs.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-40080.
| URL | Resource |
|---|---|
| https://github.com/Cacti/cacti/releases/tag/release%2F1.2.31 | Product Release Notes |
| https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq | Exploit Mitigation Vendor Advisory |
| https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq | Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-40080 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-40080
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-40080 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-40080 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jun. 29, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:cacti:cacti:*:*:*:*:*:*:*:* versions up to (excluding) 1.2.31 Added Reference Type GitHub, Inc.: https://github.com/Cacti/cacti/releases/tag/release%2F1.2.31 Types: Product, Release Notes Added Reference Type GitHub, Inc.: https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq Types: Exploit, Mitigation, Vendor Advisory Added Reference Type CISA-ADP: https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq Types: Exploit, Mitigation, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 26, 2026
Action Type Old Value New Value Added Reference https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq Added SSVC {'id': 'CVE-2026-40080', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-26T14:08:58.081501Z'} -
New CVE Received by [email protected]
Jun. 25, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Cacti', 'product': 'cacti', 'versions': [{'status': 'affected', 'version': '< 1.2.31'}]}] Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Added CWE CWE-601 Added Reference https://github.com/Cacti/cacti/releases/tag/release%2F1.2.31 Added Reference https://github.com/Cacti/cacti/security/advisories/GHSA-6gr7-53g8-vchq