The png_set_text_2 function in libpng 0.71 before 1.0.67, 1.2.x before 1.2.57, 1.4.x before 1.4.20, 1.5.x before 1.5.28, and 1.6.x before 1.6.27 allows context-dependent attackers to cause a NULL pointer dereference vectors involving loading a text chunk into a png structure, removing the text, and then adding another text chunk to the structure.

Buffer overflow in the png_set_PLTE function in libpng before 1.0.65, 1.1.x and 1.2.x before 1.2.55, 1.3.x, 1.4.x before 1.4.18, 1.5.x before 1.5.25, and 1.6.x before 1.6.20 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a small bit-depth value in an IHDR (aka image header) chunk in a PNG image. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-8126.

Buffer overflow in the png_read_IDAT_data function in pngrutil.c in libpng before 1.5.21 and 1.6.x before 1.6.16 allows context-dependent attackers to execute arbitrary code via IDAT data with a large width, a different vulnerability than CVE-2014-9495.

Heap-based buffer overflow in the png_combine_row function in libpng before 1.5.21 and 1.6.x before 1.6.16, when running on 64-bit systems, might allow context-dependent attackers to execute arbitrary code via a "very wide interlaced" PNG image.

The png_push_read_chunk function in pngpread.c in the progressive decoder in libpng 1.6.x through 1.6.9 allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via an IDAT chunk with a length of zero.

The png_do_expand_palette function in libpng before 1.6.8 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via (1) a PLTE chunk of zero bytes or (2) a NULL palette, related to pngrtran.c and pngset.c.