CVE-2021-20230

Published: 23 February 2021

A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality.

Priority

Medium

CVSS 3 base score: 7.5

Status

Package Release Status
stunnel4
Launchpad, Ubuntu, Debian
Upstream Needs triage

Ubuntu 21.04 (Hirsute Hippo) Needs triage

Ubuntu 20.10 (Groovy Gorilla) Needs triage

Ubuntu 20.04 LTS (Focal Fossa) Needs triage

Ubuntu 18.04 LTS (Bionic Beaver) Needs triage

Ubuntu 16.04 LTS (Xenial Xerus) Needs triage

Ubuntu 14.04 ESM (Trusty Tahr) Needs triage