CVE-2026-24894

FrankenPHP leaks session data between requests in worker mode

This is a cross-request data leakage vulnerability.

• Confidentiality: If an application reads $_SESSION before calling session_start(), it can access sensitive information (authentication tokens, user IDs, PII) belonging to the previous user.
• Logic Errors / Impersonation: If application logic relies on $_SESSION being empty or unset to detect a "guest" state, or checks for specific keys in $_SESSION prior to session initialization, a malicious actor (or accidental race condition) could trigger privilege escalation or user impersonation.

This affects only users running FrankenPHP in worker mode and not session_start() for each request, which is done by default by most frameworks.

The application assigns, modifies, tracks, or checks privileges incorrectly, allowing a user to gain elevated access. Typical impact: privilege escalation beyond the intended level.

Kodem intelligence

1. What is CVE-2026-24894? CVE-2026-24894 is a high-severity improper privilege management vulnerability in github.com/dunglas/frankenphp (go), affecting versions < 1.11.2. It is fixed in 1.11.2. The application assigns, modifies, tracks, or checks privileges incorrectly, allowing a user to gain elevated access.
2. Which versions of github.com/dunglas/frankenphp are affected by CVE-2026-24894? github.com/dunglas/frankenphp (go) versions < 1.11.2 is affected.
3. Is there a fix for CVE-2026-24894? Yes. CVE-2026-24894 is fixed in 1.11.2. Upgrade to this version or later.
4. Is CVE-2026-24894 exploitable, and should I be worried? Whether CVE-2026-24894 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
5. What actually determines whether CVE-2026-24894 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
6. How do I fix CVE-2026-24894? Upgrade github.com/dunglas/frankenphp to 1.11.2 or later.