modules/libpr0n/decoders/bmp/nsBMPDecoder.cpp in Mozilla Firefox before 2.0.0.12, Thunderbird before 2.0.0.12, and SeaMonkey before 1.1.8 does not properly perform certain calculations related to the mColors table, which allows remote attackers to read portions of memory uninitialized via a crafted 8-bit bitmap (BMP) file that triggers an out-of-bounds read within the heap, as demonstrated using a CANVAS element; or cause a denial of service (application crash) via a crafted 8-bit bitmap file that triggers an out-of-bounds read. NOTE: the initial public reports stated that this affected Firefox in Ubuntu 6.06 through 7.10.