libpng OOB Read in simplified API before 1.6.52
CVE-2025-66293 Published on December 3, 2025
LIBPNG has an out-of-bounds read in png_image_read_composite
LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. Prior to 1.6.52, an out-of-bounds read vulnerability in libpng's simplified API allows reading up to 1012 bytes beyond the png_sRGB_base[512] array when processing valid palette PNG images with partial transparency and gamma correction. The PNG files that trigger this vulnerability are valid per the PNG specification; the bug is in libpng's internal state management. Upgrade to libpng 1.6.52 or later.
Vulnerability Analysis
CVE-2025-66293 can be exploited with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. Public availability of a proof of concept (POC) exploit exists for CVE-2025-66293. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality, a small impact on integrity, and a high impact on availability.
Weakness Type
Out-of-bounds Read
The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.
Products Associated with CVE-2025-66293
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Affected Versions
pnggroup libpng Version < 1.6.52 is affected by CVE-2025-66293Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.