---
id: CVE-2026-111136
title: >-
  libInstPatch through 1.1.7 contains a heap out-of-bounds write vulnerability
  in the SoundFont 2 loader because ipatch_sf2_gen_is_valid() does not
  range-check generator IDs before the validity mask test
summary: >-
  libInstPatch through 1.1.7 contains a heap out-of-bounds write vulnerability
  in the SoundFont 2 loader because ipatch_sf2_gen_is_valid() does not
  range-check generator IDs before the validity mask test. Attackers can supply
  crafted SF2 f…
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H'
cwe:
  - CWE-787
vendor: swami
product: libinstpatch
affected:
  - libinstpatch <= 1.1.7
published: '2026-10-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T19:17:27.490'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-111136'
references:
  - url: 'https://github.com/swami/libinstpatch'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/libinstpatch/IpatchSF2Gen.c#L189-L205
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/libinstpatch/IpatchSF2Reader.c#L1355-L1370
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/libinstpatch/IpatchSF2Reader.c#L954-L969
    label: disclosure@vulncheck.com
  - url: 'https://hackmd.io/@haind-pwn/libinstpatch-sf2-generator-id-oob-write'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/libinstpatch-through-1.1.7-heap-out-of-bounds-write-via-ipatch-sf2-gen-is-valid
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
  - exploit-available
ingestedAt: '2026-10-15T19:25:46.410Z'
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-15T19:47:44.671476Z'
---

## Overview

libInstPatch through 1.1.7 contains a heap out-of-bounds write vulnerability in the SoundFont 2 loader because ipatch_sf2_gen_is_valid() does not range-check generator IDs before the validity mask test. Attackers can supply crafted SF2 files with out-of-range pgen or igen generator IDs to write attacker-chosen values past the zone genarray, corrupting heap memory and crashing Swami or other consumers.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.