Improper access control in Stunnel

1) Improper access control

EUVDB-ID: #VU40792

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2015-3644

CWE-ID: CWE-284 - Improper Access Control

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

Stunnel 5.00 through 5.13, when using the redirect option, does not redirect client connections to the expected server after the initial connection, which allows remote attackers to bypass authentication.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Stunnel: 5.00 - 5.13

External links

http://www.debian.org/security/2015/dsa-3299
http://www.securityfocus.com/bid/74659
http://www.securitytracker.com/id/1032324
http://www.stunnel.org/CVE-2015-3644.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.