OpenSSL up to 0.9.8/1.0.0q/1.0.1l/1.0.2 SSLv2 s2_srvr.c get_client_master_key information disclosure

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.5	$0-$5k	0.00

Summaryinfo

A vulnerability identified as critical has been detected in OpenSSL up to 0.9.8/1.0.0q/1.0.1l/1.0.2. This vulnerability affects the function get_client_master_key of the file s2_srvr.c of the component SSLv2 Handler. This manipulation causes information disclosure. The identification of this vulnerability is CVE-2016-0704. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in OpenSSL up to 0.9.8/1.0.0q/1.0.1l/1.0.2 (Network Encryption Software) and classified as critical. Affected by this vulnerability is the function get_client_master_key of the file s2_srvr.c of the component SSLv2 Handler. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

An oracle protection mechanism in the get_client_master_key function in s2_srvr.c in the SSLv2 implementation in OpenSSL before 0.9.8zf, 1.0.0 before 1.0.0r, 1.0.1 before 1.0.1m, and 1.0.2 before 1.0.2a overwrites incorrect MASTER-KEY bytes during use of export cipher suites, which makes it easier for remote attackers to decrypt TLS ciphertext data by leveraging a Bleichenbacher RSA padding oracle, a related issue to CVE-2016-0800.

The weakness was shared 03/02/2016 by Alex with University of Michigan (Website). It is possible to read the advisory at git.openssl.org. This vulnerability is known as CVE-2016-0704 since 12/15/2015. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 82783 (CentOS 5 : openssl (CESA-2015:0800) (FREAK)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CentOS Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 350021 (Amazon Linux Security Advisory for openssl098e: ALAS-2016-682).

Upgrading to version 0.9.8zf, 1.0.0r, 1.0.1m or 1.0.2a eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (111146), Tenable (82783), SecurityFocus (BID 83764†) and Vulnerability Center (SBV-57002†). The entries VDB-68520, VDB-74747, VDB-81112 and VDB-81138 are related to this item. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Network Encryption Software

Name

• OpenSSL

Version

• 0.9.8
• 1.0.0a
• 1.0.0b
• 1.0.0c
• 1.0.0d
• 1.0.0e
• 1.0.0f
• 1.0.0g
• 1.0.0h
• 1.0.0i
• 1.0.0j
• 1.0.0k
• 1.0.0l
• 1.0.0m
• 1.0.0n
• 1.0.0o
• 1.0.0p
• 1.0.0q
• 1.0.1a
• 1.0.1b
• 1.0.1c
• 1.0.1d
• 1.0.1e
• 1.0.1f
• 1.0.1g
• 1.0.1h
• 1.0.1i
• 1.0.1j
• 1.0.1k
• 1.0.1l
• 1.0.2

License

• open-source

Support

• end of life (old version)

Website

• Product: https://www.openssl.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.6

VulDB Base Score: 5.9
VulDB Temp Score: 5.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 82783
Nessus Name: CentOS 5 : openssl (CESA-2015:0800) (FREAK)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 14611
OpenVAS Name: Amazon Linux Local Check: alas-2016-682
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: OpenSSL 0.9.8zf/1.0.0r/1.0.1m/1.0.2a
Patch: ae50d8270026edf5b3c7f8aaa0c6677462b33d97

Timelineinfo

04/14/2015 🔍
04/15/2015 +1 days 🔍
12/15/2015 +245 days 🔍
02/29/2016 +76 days 🔍
03/01/2016 +1 days 🔍
03/02/2016 +0 days 🔍
03/02/2016 +0 days 🔍
03/03/2016 +1 days 🔍
03/05/2016 +2 days 🔍
07/08/2022 +2315 days 🔍

Sourcesinfo

Product: openssl.org

Advisory: RHSA-2015:0800
Researcher: Alex
Organization: University of Michigan
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-0704 (🔍)
GCVE (CVE): GCVE-0-2016-0704
GCVE (VulDB): GCVE-100-81139

OVAL: 🔍

X-Force: 111146 - OpenSSL Bleichenbacher security bypass
SecurityFocus: 83764 - OpenSSL CVE-2016-0704 Information Disclosure Vulnerability
SecurityTracker: 1035133
Vulnerability Center: 57002 - OpenSSL Remote Restriction Bypass in SSLv2 - CVE-2016-0704, Medium

See also: 🔍

Entryinfo

Created: 03/03/2016 10:19
Updated: 07/08/2022 19:34
Changes: 03/03/2016 10:19 (68), 09/01/2018 08:39 (26), 07/08/2022 19:27 (6), 07/08/2022 19:34 (1)
Complete: 🔍
Cache ID: 216:D64:103

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