Session hijacking via unrotated session identifier
Published Jun 25, 2026 · Updated Jun 25, 2026
Session fixation in Cacti 1.2.30 and earlier allows remote attackers to hijack authenticated sessions through a preset PHP session cookie. The login flow in auth_login.php and the cookie-restore and basic-auth paths in include/auth.php assign the user ID without rotating the PHP session identifier. Exploitation requires placing the identifier in a victim's browser and waiting for login; resulting access is limited to that victim's authenticated privileges.
Summary
What happened
Session fixation in Cacti 1.2.30 and earlier allows remote attackers to hijack authenticated sessions through a preset PHP session cookie. The login flow in auth_login.php and the cookie-restore and basic-auth paths in include/auth.php assign the user ID without rotating the PHP session identifier. Exploitation requires placing the identifier in a victim's browser and waiting for login; resulting access is limited to that victim's authenticated privileges.
The record
- CVE
- CVE-2026-40082
- Published
- Jun 25, 2026
- Updated
- Jun 25, 2026
- Vendor
- The Cacti Group
- Product
- Cacti
- Classifications
- CWE-384, T1550.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 25, 2026CVE publishedPublication date reported by the CVE source.
- Jun 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 1.2.31
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Upstream session-fixation reproduction procedureproof of concept · unverified
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Technologies
Your stack
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Your stack
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