Vulnerability · Published Jun 2, 2026 · Assigned by GitHub_M

CVE-2026-41412alf.io vulnerable to Arbitrary File Read and Exfil via simpleHttpClient Extension Script

Medium 4.9

In plain English

A medium-severity path traversal in alf.io from alfio-event. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).

Severity (CVSS 3.1)4.9Medium

Exploit odds (30 days)0.3%top 75.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

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, the alf.io extension sandbox injects a fully-functional HTTP client (`simpleHttpClient`) into every extension script's scope. The `postFileAndSaveResponse()` method accepts an arbitrary filesystem path as its `file` parameter and reads the file contents using `new FileInputStream(file)` with no path validation, directory restriction, or allowlist. A malicious extension script can read any file accessible to the JVM process user and exfiltrate it to an attacker-controlled server via HTTP POST. Version 2.0-M5-2606 patches the issue.

Affected products (as reported)

Vendor	Product	Versions
alfio-event	alf.io	< 2.0-M5-2606

Weakness: CWE-22, CWE-73 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

References

https://github.com/alfio-event/alf.io/security/advisories/GHSA-6m62-53cw-4373 x_refsource_CONFIRM