Heap Out-of-Bounds Read in LodePNG

Executive Summary

This vulnerability is a heap out-of-bounds read in the LodePNG library affecting the function getFilterTypesInterlaced() in lodepng_util.cpp. It occurs when processing interlaced PNG files where the decompressed IDAT data size is smaller than the declared image dimensions. The function fails to validate memory access bounds, allowing reads beyond allocated memory. This can expose adjacent heap memory or crash applications.

Useful 0 Not Useful 0

Detection Guidance

To detect this vulnerability, inspect PNG files processed by LodePNG for interlaced files with declared raster sizes larger than their IDAT stream. Use tools like file inspection utilities or custom scripts to check PNG metadata and IDAT chunk sizes. Monitor applications using LodePNG for crashes or memory leaks when processing interlaced PNGs.

Useful 0 Not Useful 0

Impact Analysis

An attacker could exploit this to disclose sensitive heap memory data or cause denial-of-service by crashing applications. The impact depends on the application using LodePNG. If the library is used in image processing software, it may leak memory contents or terminate unexpectedly when processing malicious PNG files.

Useful 0 Not Useful 0

Compliance Impact

This vulnerability could potentially impact compliance with GDPR and HIPAA by enabling unauthorized disclosure of adjacent heap memory. If exploited, it may expose sensitive data processed by applications using LodePNG, violating data protection requirements under these regulations.

Useful 0 Not Useful 0

Mitigation Strategies

Update LodePNG to the latest version where the vulnerability is patched. If updating is not possible, disable the use of interlaced PNGs in your applications or remove the getFilterTypesInterlaced function from lodepng_util.cpp. Apply strict input validation for PNG files to reject malformed interlaced files with mismatched raster and IDAT sizes.

Useful 0 Not Useful 0