Use-after-free vulnerability in the GIFReadNextExtension function in lib/pngxtern/gif/gifread.c in OptiPNG 0.6.2 and earlier allows context-dependent attackers to cause a denial of service (application crash) via a crafted GIF image that causes the realloc function to return a new pointer, which triggers memory corruption when the old pointer is accessed.

Use-after-free vulnerability in OptiPNG 0.6.4 allows remote attackers to execute arbitrary code via a crafted PNG file.

gifread.c in gif2png, as used in OptiPNG before 0.7.6, allows remote attackers to cause a denial of service (uninitialized memory read) via a crafted GIF file.

Heap-based buffer overflow in the bmp_read_rows function in pngxrbmp.c in OptiPNG before 0.7.6 allows remote attackers to cause a denial of service (out-of-bounds read or write access and crash) or possibly execute arbitrary code via a crafted image file.

Off-by-one error in the bmp_rle4_fread function in pngxrbmp.c in OptiPNG before 0.7.6 allows remote attackers to cause a denial of service (out-of-bounds read or write access and crash) or possibly execute arbitrary code via a crafted image file, which triggers a heap-based buffer overflow.

Integer overflow bug in function minitiff_read_info() of optipng 0.7.6 allows an attacker to remotely execute code or cause denial of service.

A global buffer overflow in OptiPNG 0.7.6 allows remote attackers to cause a denial-of-service attack or other unspecified impact with a maliciously crafted GIF format file, related to an uncontrolled loop in the LZWReadByte function of the gifread.c file.

OptiPNG v0.7.7 was discovered to contain a global buffer overflow via the 'buffer' variable at gifread.c.