USN-8190-1: Rack::Session vulnerability

Publication date

20 April 2026

Overview

Rack::Session could allow unintended access to network services.

Releases


Packages

Details

SeungMyung Lee discovered that Rack::Session did not properly reject
cookies upon decryption failure. A remote attacker could use this issue to
manipulate session contents and possibly gain unauthorized access.

SeungMyung Lee discovered that Rack::Session did not properly reject
cookies upon decryption failure. A remote attacker could use this issue to
manipulate session contents and possibly gain unauthorized access.

Update instructions

After a standard system update you need to restart ruby-rack-session to 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
25.10 questing ruby-rack-session –  2.1.1-0.1ubuntu0.1

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