CVE-2021-39247 : Vulnerability Insights and Analysis
Learn about CVE-2021-39247, a one-byte buffer over-read vulnerability in Zint Barcode Generator before 2.10.0. Find out the impact, affected systems, exploitation details, and mitigation steps.
Zint Barcode Generator before 2.10.0 has a one-byte buffer over-read vulnerability related to is_last_single_ascii in code1.c and rs_encode_uint in reedsol.c.
Understanding CVE-2021-39247
This CVE entry pertains to a specific vulnerability in the Zint Barcode Generator software.
What is CVE-2021-39247?
CVE-2021-39247 is a one-byte buffer over-read vulnerability found in Zint Barcode Generator before version 2.10.0. The issue is linked to is_last_single_ascii in code1.c and rs_encode_uint in reedsol.c.
The Impact of CVE-2021-39247
The vulnerability could potentially lead to information leakage, denial of service, or even remote code execution if exploited by malicious actors.
Technical Details of CVE-2021-39247
This section delves into specific technical aspects of the CVE.
Vulnerability Description
The vulnerability stems from a one-byte buffer over-read issue within Zint Barcode Generator, specifically in is_last_single_ascii function in code1.c and rs_encode_uint function in reedsol.c.
Affected Systems and Versions
- Affected Versions: Zint Barcode Generator versions before 2.10.0
- Affected Vendor: n/a
- Affected Products: n/a
Exploitation Mechanism
The vulnerability can be exploited through crafted inputs, potentially causing the application to read beyond the bounds of allocated memory, leading to unexpected behavior.
Mitigation and Prevention
In this section, we outline steps to mitigate the risks associated with CVE-2021-39247.
Immediate Steps to Take
- Upgrade Zint Barcode Generator to version 2.10.0 or newer to mitigate the vulnerability.
- Avoid opening untrusted barcode files received from unknown sources.
Long-Term Security Practices
- Regularly update and patch software to ensure the latest security fixes are applied.
- Conduct security assessments and code reviews to identify and address vulnerabilities proactively.
Patching and Updates
- Stay informed about security advisories related to Zint Barcode Generator and promptly apply recommended patches.