CVE-2026-40082
Cacti: Session Fixation via missing session_regenerate_id() after login
Description
Cacti is an open source performance and fault management framework. Versions 1.2.30 and prior have missing session_regenerate_id() after login, leading to Session Fixation. session_regenerate_id() is NOT called after successful login. The login flow at auth_login.php:203-207 directly sets $_SESSION[SESS_USER_ID] without rotating the session ID. The session cookie configuration is otherwise good (httponly=true, samesite=Strict, secure=true for HTTPS at include/global.php:513-537), but these do not prevent session fixation via same-site vectors. 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, 6:50 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.
- Verify session ID regeneration after login.
Public PoC/Exploit Available at Github
CVE-2026-40082 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
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-2026-40082.
| URL | Resource |
|---|---|
| https://github.com/Cacti/cacti/commit/2fa404e70a5702be10682555911228e8e51ba198 | Patch |
| https://github.com/Cacti/cacti/releases/tag/release%2F1.2.31 | Product Release Notes |
| https://github.com/Cacti/cacti/security/advisories/GHSA-273r-qr93-wgcp | 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-2026-40082 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-2026-40082
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).
None
Ruby PHP HTML CSS JavaScript Less SCSS Shell Perl Dockerfile
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-40082 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-40082 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/commit/2fa404e70a5702be10682555911228e8e51ba198 Types: Patch 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-273r-qr93-wgcp Types: Exploit, Mitigation, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 26, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-40082', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-26T17:50:35.387627Z'} -
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 have missing session_regenerate_id() after login, leading to Session Fixation. session_regenerate_id() is NOT called after successful login. The login flow at auth_login.php:203-207 directly sets $_SESSION[SESS_USER_ID] without rotating the session ID. The session cookie configuration is otherwise good (httponly=true, samesite=Strict, secure=true for HTTPS at include/global.php:513-537), but these do not prevent session fixation via same-site vectors. This issue has been fixed in version 1.2.31. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N Added CWE CWE-384 Added Reference https://github.com/Cacti/cacti/commit/2fa404e70a5702be10682555911228e8e51ba198 Added Reference https://github.com/Cacti/cacti/releases/tag/release%2F1.2.31 Added Reference https://github.com/Cacti/cacti/security/advisories/GHSA-273r-qr93-wgcp