FreeBSD : OpenSSL -- Client DoS due to large DH parameter (c82ecac5-6e3f-11e8-8777-b499baebfeaf)

medium Nessus Plugin ID 110504

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VPR Score: 3.6

Synopsis

The remote FreeBSD host is missing one or more security-related updates.

Description

The OpenSSL project reports :

During key agreement in a TLS handshake using a DH(E) based ciphersuite a malicious server can send a very large prime value to the client. This will cause the client to spend an unreasonably long period of time generating a key for this prime resulting in a hang until the client has finished. This could be exploited in a Denial Of Service attack.

Solution

Update the affected packages.

See Also

https://www.openssl.org/news/secadv/20180612.txt

http://www.nessus.org/u?1630b29b

Plugin Details

Severity: Medium

ID: 110504

File Name: freebsd_pkg_c82ecac56e3f11e88777b499baebfeaf.nasl

Version: 1.6

Type: local

Published: 6/13/2018

Updated: 11/10/2018

Dependencies: ssh_get_info.nasl

Risk Information

Risk Factor: Medium

VPR Score: 3.6

CVSS v2.0

Base Score: 5

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS v3.0

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:libressl, p-cpe:/a:freebsd:freebsd:libressl-devel, p-cpe:/a:freebsd:freebsd:openssl, p-cpe:/a:freebsd:freebsd:openssl-devel, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info

Patch Publication Date: 6/12/2018

Vulnerability Publication Date: 6/12/2018

Reference Information

CVE: CVE-2018-0732