CVE-2020-28248 : Security Advisory and Response

An integer overflow in the PngImg::InitStorage_() function of png-img before 3.1.0 leads to an under-allocation of heap memory and subsequently an exploitable heap-based buffer overflow when loading a crafted PNG file.

Understanding CVE-2020-28248

This CVE involves an integer overflow in a specific function of the png-img library, potentially leading to a heap-based buffer overflow.

What is CVE-2020-28248?

CVE-2020-28248 is an integer overflow vulnerability in the PngImg::InitStorage_() function of png-img before version 3.1.0. This flaw can result in an under-allocation of heap memory, creating a security risk when processing malicious PNG files.

The Impact of CVE-2020-28248

The vulnerability can be exploited by an attacker to trigger a heap-based buffer overflow, potentially leading to arbitrary code execution or denial of service.

Technical Details of CVE-2020-28248

This section provides more in-depth technical insights into the CVE.

Vulnerability Description

The vulnerability arises from an integer overflow in the PngImg::InitStorage_() function, causing inadequate memory allocation and enabling a heap-based buffer overflow.

Affected Systems and Versions

Systems using png-img library versions prior to 3.1.0 are vulnerable.

Exploitation Mechanism

An attacker can exploit this vulnerability by crafting a malicious PNG file that triggers the integer overflow, leading to a buffer overflow.

Mitigation and Prevention

Protecting systems from CVE-2020-28248 requires immediate actions and long-term security measures.

Immediate Steps to Take

Update the png-img library to version 3.1.0 or later to mitigate the vulnerability.
Avoid opening untrusted PNG files until the library is patched.

Long-Term Security Practices

Regularly update software and libraries to the latest versions to address known vulnerabilities.
Implement input validation and secure coding practices to prevent buffer overflows.

Patching and Updates

Apply patches and updates provided by the png-img library maintainers to fix the vulnerability.