Synopsis
The remote service is affected by multiple vulnerabilities.
Description
The version of OpenSSL installed on the remote host is prior to 1.1.0c. It is, therefore, affected by multiple vulnerabilities as referenced in the 1.1.0c advisory.
- There is a carry propagating bug in the Broadwell-specific Montgomery multiplication procedure in OpenSSL 1.0.2 and 1.1.0 before 1.1.0c that handles input lengths divisible by, but longer than 256 bits. Analysis suggests that attacks against RSA, DSA and DH private keys are impossible. This is because the subroutine in question is not used in operations with the private key itself and an input of the attacker's direct choice. Otherwise the bug can manifest itself as transient authentication and key negotiation failures or reproducible erroneous outcome of public-key operations with specially crafted input. Among EC algorithms only Brainpool P-512 curves are affected and one presumably can attack ECDH key negotiation. Impact was not analyzed in detail, because pre-requisites for attack are considered unlikely. Namely multiple clients have to choose the curve in question and the server has to share the private key among them, neither of which is default behaviour. Even then only clients that chose the curve will be affected. (CVE-2016-7055)
- In OpenSSL 1.1.0 before 1.1.0c, TLS connections using *-CHACHA20-POLY1305 ciphersuites are susceptible to a DoS attack by corrupting larger payloads. This can result in an OpenSSL crash. This issue is not considered to be exploitable beyond a DoS. (CVE-2016-7054)
- In OpenSSL 1.1.0 before 1.1.0c, applications parsing invalid CMS structures can crash with a NULL pointer dereference. This is caused by a bug in the handling of the ASN.1 CHOICE type in OpenSSL 1.1.0 which can result in a NULL value being passed to the structure callback if an attempt is made to free certain invalid encodings. Only CHOICE structures using a callback which do not handle NULL value are affected.
(CVE-2016-7053)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Upgrade to OpenSSL version 1.1.0c or later.
Plugin Details
File Name: openssl_1_1_0c.nasl
Agent: windows, macosx, unix
Configuration: Enable thorough checks
Supported Sensors: Nessus Agent, Nessus
Risk Information
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C
Vulnerability Information
CPE: cpe:/a:openssl:openssl
Required KB Items: installed_sw/OpenSSL
Exploit Ease: Exploits are available
Patch Publication Date: 11/10/2016
Vulnerability Publication Date: 11/10/2016