CVE-2026-35482 alf.io has an Authenticated RCE via Extension Script Sandbox Escape
An authenticated administrator can escape the extension script sandbox to execute arbitrary OS commands on the server.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-35482?
CVE-2026-35482 is a high-severity code injection vulnerability in alfio-event alf.io, published on 2 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
alf.io is an open source ticket reservation system for conferences, trade shows, workshops, and meetups. Prior to version 2.0-M5-2606, a sandbox escape vulnerability in the alf.io extension script engine allows an authenticated administrator to execute arbitrary operating system commands on the server. The extension system is intended to execute restricted JavaScript in a sandboxed Rhino environment; however, a combination of an unguarded injected Java object (`returnClass`) and an incomplete AST blocklist allows the sandbox to be fully escaped using Java reflection without triggering any validation errors. Version 2.0-M5-2606 patches the issue.
Weakness: CWE-863
Which versions are affected by CVE-2026-35482?
It affects 1 product.
Products include Alf Alf.
How do I fix CVE-2026-35482?
No fix has been published for CVE-2026-35482 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-35482 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-35482 exists.
Other vulnerabilities in alfio-event alf.io
- CVE-2023-2259 Improper Neutralization of Special Elements Used in a Template Engine in alfio-event/alf.io
- CVE-2024-25635 IDOR Vulnerability: Allowing Organization Owner to view the other Organizations API KEY and USERS
- CVE-2023-2258 Improper Neutralization of Formula Elements in a CSV File in alfio-event/alf.io
- CVE-2023-2260 Authorization Bypass Through User-Controlled Key in alfio-event/alf.io
- CVE-2024-25628 Insufficient Session Expiration in alf.io
Sources
Also known as GHSA-3w8f-mcf6-cm7h.