OpenSSL Denial-of-Service Vulnerability (CVE-2020-1971) Threat Alert

OpenSSL Denial-of-Service Vulnerability (CVE-2020-1971) Threat Alert

janeiro 5, 2021 | Adeline Zhang

Overview

On December 8, 2020, local time, OpenSSL released a security advisory disclosing a NULL pointer dereference vulnerability (CVE-2020-1971), rating the vulnerability as High-risk.

The vulnerability exists in the GENERAL_NAME_cmp function in OpenSSL. GENERAL_NAME_cmp compares different instances of a GENERAL_NAME to see if they are equal or not. When both GENERAL_NAMEs contain EDIPartyName, a NULL pointer dereference and a crash may occur, eventually causing a denial of service.

Therefore, if an attacker can control both items being compared, a crash might be triggered. For example, the attacker can trick a client or server into checking a malicious certificate against a malicious CRL.

Reference link:

https://www.openssl.org/news/secadv/20201208.txt

Affected Versions

  • OpenSSL 1.1.1
  • OpenSSL 1.0.2 (out of support)

Unaffected Version

  • OpenSSL 1.1.1i

Solution

OpenSSL has released new versions to fix the vulnerability. Affected users are advised to upgrade without delay.

The update is available at the following link:

https://www.openssl.org/source/

Statement

This advisory is only used to describe a potential risk. NSFOCUS does not provide any commitment or promise on this advisory. NSFOCUS and the author will not bear any liability for any direct and/or indirect consequences and losses caused by transmitting and/or using this advisory. NSFOCUS reserves all the rights to modify and interpret this advisory. Please include this statement paragraph when reproducing or transferring this advisory. Do not modify this advisory, add/delete any information to/from it, or use this advisory for commercial purposes without permission from NSFOCUS.

About NSFOCUS

NSFOCUS, Inc., a global network and cyber security leader, protects enterprises and carriers from advanced cyber attacks. The company’s Intelligent Hybrid Security strategy utilizes both cloud and on-premises security platforms, built on a foundation of real-time global threat intelligence, to provide multi-layered, unified and dynamic protection against advanced cyber attacks.

NSFOCUS works with Fortune Global 500 companies, including four of the world’s five largest financial institutions, organizations in insurance, retail, healthcare, critical infrastructure industries as well as government agencies. NSFOCUS has technology and channel partners in more than 60 countries, is a member of both the Microsoft Active Protections Program (MAPP), and the Cloud Security Alliance (CSA).

A wholly owned subsidiary of NSFOCUS Technologies Group Co., Ltd., the company has operations in the Americas, Europe, the Middle East and Asia Pacific.