CVE-2018-12435 : What You Need to Know

Botan versions 2.5.0 to 2.6.0, before 2.7.0, are vulnerable to a memory-cache side-channel attack on ECDSA signatures known as Return Of the Hidden Number Problem (ROHNP).

Understanding CVE-2018-12435

This CVE involves a security vulnerability in Botan versions 2.5.0 to 2.6.0 that can be exploited through a memory-cache side-channel attack on ECDSA signatures.

What is CVE-2018-12435?

Botan versions 2.5.0 to 2.6.0, prior to 2.7.0, have a vulnerability that allows attackers to exploit a memory-cache side-channel attack on ECDSA signatures. The attack is associated with specific files within the Botan library.

The Impact of CVE-2018-12435

The vulnerability in Botan can lead to the exposure of ECDSA keys if exploited by an attacker who has access to the local machine or a virtual machine on the same physical server.

Technical Details of CVE-2018-12435

Botan 2.5.0 through 2.6.0 before 2.7.0 allows a memory-cache side-channel attack on ECDSA signatures, also known as the Return Of the Hidden Number Problem (ROHNP).

Vulnerability Description

The vulnerability in Botan can be exploited through a memory-cache side-channel attack on ECDSA signatures, specifically affecting the files dsa/dsa.cpp, ec_group/ec_group.cpp, and ecdsa/ecdsa.cpp.

Affected Systems and Versions

Affected Versions: 2.5.0 to 2.6.0
Unaffected Version: 2.7.0

Exploitation Mechanism

To exploit this vulnerability and obtain an ECDSA key, the attacker must have access to either the local machine or a separate virtual machine hosted on the same physical server.

Mitigation and Prevention

It is crucial to take immediate steps to address and prevent the exploitation of this vulnerability.

Immediate Steps to Take

Update Botan to version 2.7.0 or later to mitigate the vulnerability.
Restrict access to the local machine and virtual machines to authorized personnel only.

Long-Term Security Practices

Implement strong access controls and authentication mechanisms.
Regularly monitor and audit system activities for any suspicious behavior.

Patching and Updates

Regularly check for security updates and patches for the Botan library to ensure protection against known vulnerabilities.