Home / mailings [USN-9058-1] Action Pack Page Caching vulnerability
Posted on 12 November 2026
Ubuntu Security==========================================================================Ubuntu Security Notice USN-9058-1
November 11, 2026
ruby-actionpack-page-caching vulnerability
==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
Summary:
Action Pack Page Caching could be made to overwrite files if it received
specially crafted network traffic.
Software Description:
- ruby-actionpack-page-caching: static page caching for Action Pack
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.
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 20.04 LTS
ruby-actionpack-page-caching 1.1.0-1ubuntu0.1~esm1
Available with Ubuntu Pro
Ubuntu 18.04 LTS
ruby-actionpack-page-caching 1.0.2-4ubuntu0.18.04.1~esm1
Available with Ubuntu Pro
Ubuntu 16.04 LTS
ruby-actionpack-page-caching 1.0.2-4ubuntu0.16.04.1~esm1
Available with Ubuntu Pro
In general, a standard system update will make all the necessary changes.
References:
https://ubuntu.com/security/notices/USN-9058-1
CVE-2020-8159
--===============5945469721921700724==Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature
