Out-of-bounds write in libInstPatch SoundFont 2 loader
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
libInstPatch through 1.1.7 from swami contains a heap out-of-bounds write in its SoundFont 2 loader (CWE-787). The function ipatch_sf2_gen_is_valid() does not range-check generator IDs before its validity mask test. If a user opens a crafted SF2 file with out-of-range generator IDs, an attacker can write chosen values past the zone genarray, corrupting heap memory and crashing Swami or other consumers.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
The sources list no fixed version for libInstPatch.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Vendor assessments
Timeline
- 2026-10-16 Threatist record created from CVE-2026-111136
- 2026-10-16 Affected versions changed · Red Hat
- 2026-10-16 CVSS score added · Red Hat
References
Other 5
- https://hackmd.io/@haind-pwn/libinstpatch-sf2-generator-id-oob-write
- https://github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/libinstpatch/IpatchSF2Gen.c#L189-L205
- https://github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/libinstpatch/IpatchSF2Reader.c#L1355-L1370
- https://github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/libinstpatch/IpatchSF2Reader.c#L954-L969
- https://github.com/swami/libinstpatch
Sources
- CVE-2026-111136 · CVE Program
- CVE-2026-111136 · NVD
- FIRST EPSS
- CVE-2026-111136 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences