CVE-2026-120456: L-SMASH through 2.14.5 Heap Out-of-Bounds Write via hdlr and url Boxes

L-SMASH through 2.14.5 contains a heap out-of-bounds write vulnerability in isomreadhdlr() and isomreaddrefentry() in core/read.c triggered by oversized box sizes. Attackers can supply crafted MP4 or MOV files declaring hdlr or url box sizes larger than remaining data, stalling the stream position and corrupting heap memory to crash applications.