CVE-2019-3857 : Vulnerability Insights and Analysis
Learn about CVE-2019-3857, a critical vulnerability in libssh2 before 1.8.1, allowing remote attackers to execute arbitrary code on client systems. Find mitigation steps and updates here.
A vulnerability was found in libssh2 prior to version 1.8.1, involving an integer overflow issue that could lead to an out-of-bounds write scenario. This flaw could potentially allow an attacker to execute arbitrary code on the client system.
Understanding CVE-2019-3857
This CVE involves a critical vulnerability in libssh2 that could be exploited by a remote attacker to compromise the client system.
What is CVE-2019-3857?
CVE-2019-3857 is an integer overflow flaw in libssh2 before version 1.8.1. The vulnerability arises when parsing SSH_MSG_CHANNEL_REQUEST packets with an exit signal, potentially leading to an out-of-bounds write scenario.
The Impact of CVE-2019-3857
The impact of this vulnerability is rated as HIGH, with a CVSS base score of 7.5. If successfully exploited, an attacker could execute arbitrary code on the client system, compromising confidentiality, integrity, and availability.
Technical Details of CVE-2019-3857
This section provides more technical insights into the vulnerability.
Vulnerability Description
The vulnerability in libssh2 before version 1.8.1 involves an integer overflow issue when parsing SSH_MSG_CHANNEL_REQUEST packets with an exit signal, potentially leading to an out-of-bounds write scenario.
Affected Systems and Versions
- Product: libssh2
- Vendor: The libssh2 Project
- Affected Version: 1.8.1
Exploitation Mechanism
The flaw can be exploited by a remote attacker who compromises an SSH server. Upon a user establishing a connection with the server, the attacker may execute arbitrary code on the client system.
Mitigation and Prevention
To address CVE-2019-3857, follow these mitigation strategies:
Immediate Steps to Take
- Update libssh2 to version 1.8.1 or later to mitigate the vulnerability.
- Monitor vendor advisories for patches and updates.
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
- Apply patches provided by the vendor promptly to address the vulnerability and enhance system security.