CVE-2020-6851 Explained : Impact and Mitigation

OpenJPEG through 2.3.1 has a heap-based buffer overflow vulnerability due to a lack of validation in opj_t1_clbl_decode_processor in openjp2/t1.c.

Understanding CVE-2020-6851

What is CVE-2020-6851?

CVE-2020-6851 is a heap-based buffer overflow vulnerability found in OpenJPEG through version 2.3.1. The issue arises from inadequate validation in the opj_t1_clbl_decode_processor function in openjp2/t1.c.

The Impact of CVE-2020-6851

This vulnerability could be exploited by an attacker to execute arbitrary code or cause a denial of service (DoS) on systems running the affected versions of OpenJPEG.

Technical Details of CVE-2020-6851

Vulnerability Description

The heap-based buffer overflow occurs in the opj_t1_clbl_decode_processor function in openjp2/t1.c due to the lack of proper validation of opj_j2k_update_image_dimensions.

Affected Systems and Versions

Product: Not applicable
Vendor: Not applicable
Versions affected: All versions up to 2.3.1

Exploitation Mechanism

The vulnerability can be exploited by a remote attacker to trigger the buffer overflow, potentially leading to the execution of malicious code or a DoS condition.

Mitigation and Prevention

Immediate Steps to Take

Apply the latest security updates provided by the OpenJPEG project.
Consider implementing network security measures to prevent unauthorized access to vulnerable systems.

Long-Term Security Practices

Regularly monitor security mailing lists and vendor advisories for any updates related to OpenJPEG vulnerabilities.
Conduct regular security assessments and penetration testing to identify and address potential vulnerabilities.

Patching and Updates

Update OpenJPEG to version 2.3.2 or later to mitigate the heap-based buffer overflow vulnerability.