CVE-2021-42716 Explained : Impact and Mitigation
Learn about CVE-2021-42716, a vulnerability in stb_image.h 2.27 leading to a buffer overflow. Find out the impact, affected systems, exploitation mechanism, and mitigation steps.
An issue in stb_image.h 2.27 can lead to a buffer overflow, potentially crashing a service or exposing heap data.
Understanding CVE-2021-42716
What is CVE-2021-42716?
This CVE identifies a vulnerability in stb_image.h 2.27 where 16-bit PGM files are incorrectly interpreted as 8-bit, leading to a buffer overflow.
The Impact of CVE-2021-42716
The vulnerability could allow an attacker to crash a service using stb_image or extract up to 1024 bytes of non-consecutive heap data.
Technical Details of CVE-2021-42716
Vulnerability Description
The PNM loader in stb_image.h 2.27 incorrectly handles 16-bit PGM files, causing a buffer overflow during conversion to RGBA.
Affected Systems and Versions
- Product: not applicable
- Vendor: not applicable
- Version: not applicable
Exploitation Mechanism
The vulnerability arises when 16-bit PGM files are misinterpreted as 8-bit, leading to a buffer overflow when later processed as 16-bit data.
Mitigation and Prevention
Immediate Steps to Take
- Update stb_image.h to the latest version
- Monitor for any unusual service crashes or heap data exposures
Long-Term Security Practices
- Conduct regular security audits and code reviews
- Implement sandboxing to restrict file system access
Patching and Updates
Apply the patches provided by the vendor to address the buffer overflow issue.