WildMIDI through 0.5.0 contains a heap out-of-bounds read vulnerability in the HMP parser _WM_ParseNewHmp() that allows attackers to read beyond buffers via underflowed chunk lengths. Attackers can supply a crafted .hmp file with a chunk length of 0-12 that wraps to roughly 4 GB, crashing applications or exposing heap bytes through WildMidi_GetInfo().
https://hackmd.io/@haind-pwn/wildmidi-hmp-chunk-length-underflow-oob-read
Published: 2026-10-15
Updated: 2026-10-16
Base Score: 5.6
Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:C
Severity: Medium
Base Score: 6.1
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
Severity: Medium
Base Score: 6.9
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00129