CVE-2019-3856 Explained : Impact and Mitigation
Learn about CVE-2019-3856, a critical vulnerability in libssh2 before 1.8.1, allowing remote code execution. Find mitigation steps and long-term security practices here.
A vulnerability in libssh2 prior to version 1.8.1 has been identified, involving an integer overflow issue during the parsing of keyboard prompt requests. This flaw could potentially result in an out-of-bounds write, allowing a malicious actor to execute arbitrary code on the client system.
Understanding CVE-2019-3856
This CVE involves a critical vulnerability in libssh2 that could lead to remote code execution.
What is CVE-2019-3856?
CVE-2019-3856 is an integer overflow flaw in libssh2 before version 1.8.1, affecting the parsing of keyboard prompt requests during SSH connections.
The Impact of CVE-2019-3856
The vulnerability poses a high risk, with a CVSS base score of 7.5 (High severity). It could allow a remote attacker to execute arbitrary code on the client system.
Technical Details of CVE-2019-3856
This section provides more in-depth technical insights into the CVE.
Vulnerability Description
The flaw in libssh2 before version 1.8.1 involves an integer overflow issue during the parsing of keyboard prompt requests, potentially leading to an out-of-bounds write.
Affected Systems and Versions
- Product: libssh2
- Vendor: The libssh2 Project
- Affected Version: 1.8.1
Exploitation Mechanism
- Attack Complexity: High
- Attack Vector: Network
- Privileges Required: None
- User Interaction: Required
- Scope: Unchanged
- Confidentiality, Integrity, and Availability Impact: High
Mitigation and Prevention
Protecting systems from CVE-2019-3856 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Update libssh2 to version 1.8.1 or later to mitigate the vulnerability.
- Monitor for any signs of unauthorized access or malicious activities.
Long-Term Security Practices
- Regularly update software and apply security patches promptly.
- Implement network segmentation and access controls to limit the attack surface.
Patching and Updates
- Stay informed about security advisories and updates from the vendor.
- Follow best practices for secure SSH configurations and user authentication.