CVE-2026-128990

xschem 2.9.9 through 3.4.7 contains a heap out-of-bounds write vulnerability in read dataset() in src/rawtovcd.c due to an unchecked variable index. Attackers can supply a crafted ngspice .raw file that, when converted with rawtovcd, writes file-controlled heap pointers at chosen signed offsets, corrupting heap memory.