8.0
HIGH CVSS 3.1
CVE-2026-35482
alf.io has an Authenticated RCE via Extension Script Sandbox Escape
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.

INFO

Published Date :

June 2, 2026, 11:16 p.m.

Last Modified :

June 2, 2026, 11:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-35482 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update alf.io to version 2.0-M5-2606 or later to patch the sandbox escape vulnerability.
  • Update alf.io to version 2.0-M5-2606 or later.
  • Remove or audit untrusted extension scripts.
  • Restrict administrator access to trusted users.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-35482.

URL Resource
https://github.com/alfio-event/alf.io/security/advisories/GHSA-3w8f-mcf6-cm7h
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-35482 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-35482 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-35482 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-35482 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jun. 02, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
    Added CWE CWE-863
    Added Reference https://github.com/alfio-event/alf.io/security/advisories/GHSA-3w8f-mcf6-cm7h
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.