CVE-2026-24894·PHP vulnerability
FrankenPHP is a modern application server for PHP. Prior to 1.11.2, when running FrankenPHP in worker mode, the $_SESSION superglobal is not correctly reset between requests. This allows a subsequent request processed by the same worker to access the $_SESSION data of the previous request (potentially belonging to a different user) before session_start() is called. This vulnerability is fixed in 1.11.2.
- Severity
- high
- Software
- PHP
- Fixed in
- 1.11.2
- Published
- 2026-02-12
Affected versions
Until: 1.11.2
Fixed in: 1.11.2
How to fix this CVE
FrankenPHP running in worker mode prior to version 1.11.2 fails to properly isolate session data between concurrent requests, enabling cross-user session leakage. Immediately upgrade FrankenPHP to 1.11.2 or later to ensure session superglobals are correctly reset between worker request cycles. If you cannot upgrade immediately, disable worker mode or implement manual session cleanup between requests as a temporary mitigation.
sudo dnf update phpDefensia detects this vulnerability
How to check if you are affected
- Step 1: Check the installed FrankenPHP version by running: php -v | grep -i frankenphp or composer show symfony/runtime:* | grep frankenphp
- Step 2: Verify if FrankenPHP is running in worker mode by checking your application's configuration file (typically docker-compose.yml, Dockerfile, or .frankenphp.yml) for 'worker' directives
- Step 3: Search application logs (php-error.log, access.log) for patterns indicating session data from different users being accessed in the same request, or review application-level session logs for unexpected $_SESSION contents
- Step 4: After upgrading to 1.11.2+, confirm the update with php -v and restart all FrankenPHP worker processes (docker restart or systemctl restart php-fpm)
FAQ
What is CVE-2026-24894?
This vulnerability affects FrankenPHP's worker mode, which reuses PHP processes across multiple HTTP requests for performance. Due to improper cleanup, the $_SESSION superglobal from one request remains accessible in the next request processed by the same worker, potentially exposing another user's session data before session_start() is invoked.
Is CVE-2026-24894 being actively exploited?
No, this vulnerability is not currently listed on the CISA KEV catalog and has no public exploits available. However, the attack surface is significant in high-traffic environments where worker mode concurrency increases the likelihood of cross-user session collisions.
What versions of PHP/FrankenPHP are affected by CVE-2026-24894?
All versions of FrankenPHP prior to 1.11.2 are vulnerable. The issue affects the application server layer, not PHP core itself, so you must specifically check FrankenPHP's release version.
How do I check if my server is vulnerable to CVE-2026-24894?
Run 'php -v' and look for FrankenPHP version information; if it shows version < 1.11.2, you are vulnerable. Additionally, check your deployment configuration to confirm worker mode is enabled (grep -r 'worker' docker-compose.yml Dockerfile .frankenphp.yml 2>/dev/null).
Does Defensia detect CVE-2026-24894?
Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If FrankenPHP is installed on a monitored server, CVE-2026-24894 will appear in your dashboard with remediation steps.
Related PHP CVEs
References
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