Vulnerability · Published Jun 25, 2026 · Assigned by GitHub_M

CVE-2026-40082Cacti: Session Fixation via missing session_regenerate_id() after login

Medium 5.4

In plain English

A medium-severity session fixation in cacti from Cacti. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.4Medium
Exploit odds (30 days)0.3%top 74.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12cactino fix listedDEBIAN-CVE-2026-40082
Debian:13cactino fix listedDEBIAN-CVE-2026-40082
Debian:14cacti1.2.31+ds1-1DEBIAN-CVE-2026-40082
Ubuntu:24.04:LTScactino fix listedUBUNTU-CVE-2026-40082
Ubuntu:25.10cactino fix listedUBUNTU-CVE-2026-40082
Ubuntu:26.04:LTScactino fix listedUBUNTU-CVE-2026-40082
Ubuntu:26.10cactino fix listedUBUNTU-CVE-2026-40082

Affected products (as reported)

VendorProductVersions
Cacti cacti < 1.2.31

Weakness: CWE-384 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

References