Buffer overflow in Swami Libinstpatch
CVE-2026-111136
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@haind-pwn/libinstpatch-sf2-generator-id-oob-write (technical-description)
- github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/lib… (technical-description)
- github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/lib… (technical-description)
- github.com/swami/libinstpatch/blob/4ff1939ccc24de204d41b3ab734fc1aece919184/lib… (technical-description)
- github.com/swami/libinstpatch (product)
- www.vulncheck.com/advisories/libinstpatch-through-1.1.7-heap-out-of-bounds-writ… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-111136?
- CVE-2026-111136 is a medium-severity vulnerability in Swami Libinstpatch, classified under Out-of-bounds Write. CVSS score: 6.1/10. Published 2026-10-15.
- How severe is CVE-2026-111136?
- Medium severity. CVSS v3 base score is 6.1 out of 10.