vulnerability
Gentoo Linux: CVE-2021-20230: stunnel: Improper certificate validation
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:N/AC:L/Au:N/C:P/I:N/A:N) | Feb 23, 2021 | May 28, 2021 | Mar 31, 2026 |
Severity
5
CVSS
(AV:N/AC:L/Au:N/C:P/I:N/A:N)
Published
Feb 23, 2021
Added
May 28, 2021
Modified
Mar 31, 2026
Description
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.
Solution
gentoo-linux-upgrade-net-misc-stunnel
Rapid7 Labs
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