CVE-2021-42781 Explained : Impact and Mitigation

Heap buffer overflow issues were found in Opensc before version 0.22.0 in pkcs15-oberthur.c that could potentially crash programs using the library.

Understanding CVE-2021-42781

What is CVE-2021-42781?

CVE-2021-42781 refers to heap buffer overflow vulnerabilities discovered in Opensc prior to version 0.22.0. These vulnerabilities are located in pkcs15-oberthur.c and have the potential to cause program crashes when utilizing the Opensc library.

The Impact of CVE-2021-42781

These vulnerabilities could be exploited by malicious actors to crash programs utilizing Opensc, leading to denial of service (DoS) conditions or potentially enabling arbitrary code execution.

Technical Details of CVE-2021-42781

Vulnerability Description

Type: Heap buffer overflow
Location: pkcs15-oberthur.c
Severity: High

Affected Systems and Versions

Opensc version 0.22.0 is confirmed to be impacted by these vulnerabilities.

Exploitation Mechanism

The vulnerabilities can be triggered by providing specially crafted input, leading to uncontrolled data manipulation and potential program crashes.

Mitigation and Prevention

Immediate Steps to Take

Update Opensc to version 0.22.0 or later to address the heap buffer overflow issues.
Monitor vendor advisories and security mailing lists for related updates.

Long-Term Security Practices

Implement secure coding practices to prevent buffer overflows.
Conduct regular security assessments and code reviews to identify and address vulnerabilities.

Patching and Updates

Apply security patches promptly to prevent exploitation of known vulnerabilities in Opensc.