Improper Certificate Validation in urllib3

1) Improper Certificate Validation

EUVDB-ID: #VU39948

Risk: Low

CVSSv3.1: 3.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2016-9015

CWE-ID: CWE-295 - Improper Certificate Validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

Versions 1.17 and 1.18 of the Python urllib3 library suffer from a vulnerability that can cause them, in certain configurations, to not correctly validate TLS certificates. This places users of the library with those configurations at risk of man-in-the-middle and information leakage attacks. This vulnerability affects users using versions 1.17 and 1.18 of the urllib3 library, who are using the optional PyOpenSSL support for TLS instead of the regular standard library TLS backend, and who are using OpenSSL 1.1.0 via PyOpenSSL. This is an extremely uncommon configuration, so the security impact of this vulnerability is low.

Mitigation

Install update from vendor's website.

Vulnerable software versions

urllib3: 1.17 - 1.18

External links

http://www.openwall.com/lists/oss-security/2016/10/27/6
http://www.securityfocus.com/bid/93941

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.