Summary
The TIM (PSX TIM) image parser in ImageMagick contains a critical integer overflow vulnerability in the ReadTIMImage function (coders/tim.c). The code reads width and height (16-bit values) from the file header and calculates image_size = 2 * width * height without checking for overflow.
On 32-bit systems (or where size_t is 32-bit), this calculation can overflow if width and height are large (e.g., 65535), wrapping around to a small value. This results in a small heap allocation via AcquireQuantumMemory and later operations relying on the dimensions can trigger an out of bounds read.
Vulnerable Code
File: coders/tim.c
width=ReadBlobLSBShort(image); height=ReadBlobLSBShort(image); image_size=2*width*height; // Line 234 - NO OVERFLOW CHECK!
Impact
This vulnerability can lead to Arbitrary Memory Disclosure due to an out of bounds read on 32-bit systems.
References
Sumitshah00Reporter
Summary
The TIM (PSX TIM) image parser in ImageMagick contains a critical integer overflow vulnerability in the
ReadTIMImagefunction (coders/tim.c). The code readswidthandheight(16-bit values) from the file header and calculatesimage_size = 2 * width * heightwithout checking for overflow.On 32-bit systems (or where
size_tis 32-bit), this calculation can overflow ifwidthandheightare large (e.g., 65535), wrapping around to a small value. This results in a small heap allocation viaAcquireQuantumMemoryand later operations relying on the dimensions can trigger an out of bounds read.Vulnerable Code
File:
coders/tim.cImpact
This vulnerability can lead to Arbitrary Memory Disclosure due to an out of bounds read on 32-bit systems.
References