#VU2972 Information disclosure in OpenSSL


Published: -0001-11-30 | Updated: 2017-12-21

Vulnerability identifier: #VU2972

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2016-0701

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenSSL
Server applications / Encryption software

Vendor: OpenSSL Software Foundation

Description
The vulnerability allows a remote attacker to obtain potentially sensitive information.

The vulnerability exists due to DH_check_pub_key() function in crypto/dh/dh_check.c in OpenSSL 1.0.2 before 1.0.2f does not ensure that prime numbers are appropriate for Diffie-Hellman (DH) key exchange, which makes it easier for remote attackers to discover a private DH exponent by making multiple handshakes with a peer that chose an inappropriate number, as demonstrated by a number in an X9.42 file.

Mitigation
Update to version 1.0.2f.

Vulnerable software versions

OpenSSL: 1.0.2 - 1.0.2e


External links
http://www.openssl.org/news/secadv/20160128.txt


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.


Latest bulletins with this vulnerability