As sent to v-s ===== The sun bitmap decoder is vulnerable to multiple heap buffer overflows due to the absence of bounds checking and unchecked arithmetic operations on attacker supplied values. The DecodeImage() routine from sun.c, line ~170 performs no bounds checking on the inner rle decoding loop, allowing an attacker to use a runlength encoded payload to overflow the destination buffer. ReadSUNImage() from sun.c, line ~206, performs no range checking on attacker supplied values before using them in arithmetic operations used to allocate memory for decoded image data. A particularly favourable heap layout (callbacks/function pointers easily within reach) results in a trivially exploitable heap overflow. line 299: bytes_per_line=2*(sun_info.width*sun_info.depth+15)/16; sun_pixels=(unsigned char *) AcquireMagickMemory(bytes_per_line*height); line ~382: sun_data=(unsigned char *) AcquireMagickMemory((size_t) sun_info.length*sizeof(*sun_data)); The xcf "GIMP Image" decoder suffers from multiple buffer overflows, including a heap and a stack overflow. Both of these are exploitable to execute arbitrary code by supplying an malformed image. The stack buffer overflow is in the PROP_USER_UNIT handling, line ~1097 of xcf.c, where a fixed 1000 byte stack buffer receives a string of length specified by an attacker via the ReadBlobStringWithLongSize() function. The same non-bounds-checking function is used to read the Layer Name onto a heap buffer. This vulnerability also looks exploitable. Possible fix and testcases attached. Please credit "Tavis Ormandy, Google Security Team" in any advisories relating to these issues. ========
Created attachment 94933 [details] sun demo
Created attachment 94934 [details] xcf demo
Created attachment 94935 [details, diff] patch
Karol please advise and patch as necessary.
*** This bug has been marked as a duplicate of 143533 ***
