1. Ubuntu Security Notices
  2. USN-6901-1

USN-6901-1: stunnel vulnerability

Publication date

18 July 2024

Overview

stunnel could allow unintended access to network services.

Releases

Packages

  • stunnel4 - Universal SSL tunnel for network daemons

Details

It was discovered that stunnel did not properly validate client
certificates when configured to use both the redirect and verifyChain
options. A remote attacker could potentially use this issue to obtain
sensitive information by accessing the tunneled service.

It was discovered that stunnel did not properly validate client
certificates when configured to use both the redirect and verifyChain
options. A remote attacker could potentially use this issue to obtain
sensitive information by accessing the tunneled service.

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 focal stunnel4 –  3:5.56-1ubuntu0.2
18.04 bionic stunnel4 –  3:5.44-1ubuntu3+esm1  

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References

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