Code execution via undersized decompression buffer

Out-of-bounds write in GTKWave 3.3.115 allows attackers to execute arbitrary code by inducing a user to open a crafted LXT2 file. In lxt2_rd_iter_blocks, the parser allocates pnt from the file-controlled b->uncompressed_siz value but gives zlib the unchecked unclen value as output capacity, so decompression writes past the heap allocation. Exploitation requires user interaction with a malicious waveform file and can compromise the process rather than a network service.