CVE-2023-40216 Explained : Impact and Mitigation

OpenBSD 7.3 before errata 014 is missing an argument-count bounds check in console terminal emulation, potentially leading to a kernel crash. Learn about the impact, technical details, and mitigation steps for this CVE.

Understanding CVE-2023-40216

This section provides an overview of the CVE-2023-40216 vulnerability.

What is CVE-2023-40216?

The CVE-2023-40216 vulnerability in OpenBSD 7.3 before errata 014 arises from a lack of argument-count bounds checking in console terminal emulation. Attackers could exploit this flaw by sending crafted DCS or CSI terminal escape sequences, resulting in memory access errors and potential system crashes.

The Impact of CVE-2023-40216

The impact of CVE-2023-40216 includes the risk of incorrect memory access and kernel crashes on affected systems, which could lead to denial of service (DoS) conditions, system instability, and possible exploitation by malicious actors.

Technical Details of CVE-2023-40216

Explore the technical aspects of the CVE-2023-40216 vulnerability.

Vulnerability Description

The vulnerability originates from a missing argument-count bounds check in OpenBSD 7.3 console terminal emulation, allowing adversaries to trigger kernel crashes through specially crafted DCS or CSI escape sequences.

Affected Systems and Versions

The affected system is OpenBSD 7.3 before errata 014. All versions preceding this update are vulnerable to the exploitation of the argument-count bounds check issue.

Exploitation Mechanism

By sending maliciously crafted DCS or CSI terminal escape sequences to a vulnerable OpenBSD 7.3 system, attackers can trigger memory access errors and potentially crash the kernel, leading to system instability.

Mitigation and Prevention

Discover the steps to mitigate and prevent the CVE-2023-40216 vulnerability.

Immediate Steps to Take

Ensure that OpenBSD 7.3 systems are updated with errata 014 to patch the argument-count bounds check issue in the console terminal emulation. Implement network segmentation and access controls to reduce the risk of exploitation.

Long-Term Security Practices

Regularly monitor security advisories for OpenBSD updates and apply patches promptly to address known vulnerabilities. Conduct security assessments and audits to identify and remediate weaknesses in system configurations.

Patching and Updates

Stay informed about security patches released by OpenBSD and other relevant sources. Establish a routine patching schedule to keep systems up to date with the latest fixes and enhancements.