CVE-2026-121941 (GCVE-0-2026-121941)

Vulnerability from cvelistv5 – Published: 2026-11-04 12:31 – Updated: 2026-11-04 20:18
VLAI
Title
libmt32emu before 2.8.4 Heap Buffer Overflow via MidiStreamParserImpl::parseSysex
Summary
libmt32emu before 2.8.4 contains a heap buffer overflow vulnerability in MidiStreamParserImpl::parseSysex that allows attackers to write past a heap allocation by supplying oversized unterminated SysEx messages. Attackers can feed more than 32768 SysEx data bytes through the mt32emu_parse_stream API via MIDI files, ports, or sequencer clients to corrupt heap memory and crash the application.
Severity
8.5 (High)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-04 20:17 UTC
CWE
  • CWE-122 - Heap-based Buffer Overflow
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
munt libmt32emu Affected: 0 , < 2.8.4 (semver)
Create a notification for this product.
Date Public
2026-11-01 10:29
Credits
HaiND from the Post and Telecommunication Institute of Technology
Show details on NVD website
To clipboard 

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