USN-9058-1: Action Pack Page Caching vulnerability

Publication date

11 November 2026

Overview

Action Pack Page Caching could be made to overwrite files if it received specially crafted network traffic.


Packages

Details

It was discovered that Action Pack Page Caching incorrectly handled certain
request paths when writing cached pages. A remote attacker could possibly
use this issue to write arbitrary files to the web server, and possibly
execute arbitrary code.

It was discovered that Action Pack Page Caching incorrectly handled certain
request paths when writing cached pages. A remote attacker could possibly
use this issue to write arbitrary files to the web server, and possibly
execute arbitrary code.

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
20.04 LTS focal ruby-actionpack-page-caching –  1.1.0-1ubuntu0.1~esm1  
18.04 LTS bionic ruby-actionpack-page-caching –  1.0.2-4ubuntu0.18.04.1~esm1  
16.04 LTS xenial ruby-actionpack-page-caching –  1.0.2-4ubuntu0.16.04.1~esm1

Reduce your security exposure

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