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.
References (3)
Core 3
Core References
Issue Tracking, Third Party Advisory x_refsource_misc
https://bugzilla.redhat.com/show_bug.cgi?id=1925226
Patch, Third Party Advisory x_refsource_misc
https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9
Third Party Advisory vendor-advisory
x_refsource_gentoo
https://security.gentoo.org/glsa/202105-02
Scores
CVSS v3
7.5
EPSS
0.0021
EPSS Percentile
43.1%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Details
CWE
CWE-295
Status
published
Products (1)
stunnel/stunnel
< 5.57
Published
Feb 23, 2021
Tracked Since
Feb 18, 2026