EUVD-2026-102263Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessCraft SF2 with out-of-range generator IDs
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DeliveryDeliver file to victim via download or pack
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ExploitVictim loads SoundFont in Swami/libInstPatch consumer
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ExecutionValidity check skips range test
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PersistOut-of-bounds heap write past genarray
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ImpactHeap corruption and process crash
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Bounds checking, write limits
MITRE ATT&CK
2 techniques across 2 tactics: Execution, Privilege Escalation The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires a victim to open or load an attacker-crafted SoundFont 2 (.sf2) file in Swami or another application that uses libInstPatch through 1.1.7 to parse SF2 data; the malicious file must contain out-of-range pgen or igen generator IDs that bypass the missing range check in ipatch_sf2_gen_is_valid(). No special product configuration or non-default mode is required - any default SF2-loading code path is affected. Limiting factors: the vector is local (the file must reach and be opened by the victim), it depends on user interaction (loading the untrusted SoundFont), and reachability is bounded to software that actually consumes libInstPatch's SF2 loader, which is specialist audio tooling rather than broadly deployed infrastructure. |
| Impact | This is a genuine but moderate-priority memory-corruption flaw, correctly rated medium (CVSS 4.0 base 6.9). The vector CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P tells the real story: exploitation is local and file-driven, not network-reachable, and requires a victim to passively load a malicious SoundFont (UI:P). Impact is skewed toward availability (VA:H, reliable crash of Swami or other consumers) with only limited integrity impact (VI:L) and no confidentiality impact (VC:N) - consistent with a CWE-787 heap out-of-bounds write of attacker-chosen values past the zone genarray. No EPSS score, no CISA KEV listing, and no confirmed public exploit code were provided, so there is no evidence of active or widespread exploitation; a detailed technical writeup exists on hackmd but that is reconnaissance-grade analysis, not a confirmed weaponized exploit. The honest conclusion: a real and credible bug worth patching in any workflow that ingests untrusted SF2 files, but not an emergency - the local, user-interaction-gated vector and niche audio-tooling footprint keep real-world risk low-to-moderate. The signals here are internally consistent (no CVSS-versus-description conflict); the main open question is whether the heap write is controllable enough for code execution beyond the documented crash. |
| Exploit ScenarioDerived | An attacker distributes a malicious SoundFont 2 (.sf2) file - for example via a shared instrument pack or download - containing out-of-range pgen/igen generator IDs. When a victim opens it in Swami or any application built on libInstPatch (through 1.1.7), ipatch_sf2_gen_is_valid() skips the range check and the loader writes attacker-chosen values past the zone genarray, corrupting the heap and crashing the process. A public technical writeup details the flaw, but no confirmed public exploit code was identified in the source data. |
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Alert meAnalysisAIv1 – Oct 15, 2026
Heap out-of-bounds write in libInstPatch through 1.1.7 allows a crafted SoundFont 2 (.sf2) file to corrupt process memory when a victim loads it in Swami or any other application that uses the library's SF2 loader. The flaw lives in ipatch_sf2_gen_is_valid(), which fails to range-check pgen or igen generator IDs before the validity-mask test, so out-of-range IDs cause values to be written past the zone genarray into adjacent heap memory, crashing or potentially corrupting the consumer. The vector is local and requires user interaction (the victim must open the untrusted file), no public exploit has been identified at time of analysis, and the issue is not listed in CISA KEV, though a public technical writeup describing the root cause is available.
RemediationAI
No vendor-released patch was identified at time of analysis, so no fixed libInstPatch version can be cited; the correct patch is a bounds check on the generator ID inside ipatch_sf2_gen_is_valid() before the validity-mask test, and administrators should track the upstream repository at github.com/swami/libinstpatch plus the VulnCheck advisory (vulncheck.com/advisories/libinstpatch-through-1.1.7-heap-out-of-bounds-write-via-ipatch-sf2-gen-is-valid) and their distribution's package tracker for a corrected build, upgrading as soon as one ships. Until then, treat all .sf2 files from untrusted sources as hazardous: do not open or batch-parse them in Swami or any libInstPatch-based tool, and if parsing is operationally unavoidable, do it inside an unprivileged sandbox or container with no network access and a hardened heap allocator, accepting the trade-off that sandboxing adds friction and can break plug-in or audio-device access, and that hardening allocators (for example ASan in test builds or hardened malloc in production) turn silent corruption into a fast abort rather than preventing it. File-level validation or re-authoring of SF2 assets through a trusted converter before loading reduces exposure but is only effective if the sanitiser itself does not use the vulnerable generator-parsing code path, and restricting which users and machines are permitted to import third-party sound banks limits blast radius at the cost of user convenience.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
libInstPatch is a C/GObject library for reading, writing and manipulating instrument patch formats, and its SoundFont 2 (SF2) reader is the component at fault. An SF2 file is a RIFF-based sampled-instrument container whose presets and instruments are described by generators: preset-level pgen and instrument-level igen entries stored in per-zone genarray structures and addressed by generator ID. The vulnerable helper ipatch_sf2_gen_is_valid() (IpatchSF2Gen.c, around lines 189-205) tests a generator ID against a validity mask without first confirming that the ID is within the array bounds; the two reader call sites (IpatchSF2Reader.c, around lines 954-969 and 1355-1370) feed attacker-controlled IDs from the parsed file into that path. Because the check is missing, an out-of-range ID passes validation and the subsequent generator write occurs outside the zone genarray, which is a classic CWE-787 out-of-bounds write with heap-memory corruption as the consequence. The CPE cpe:2.3:a:swami:libinstpatch:*:*:*:*:*:*:*:* maps to the project's upstream namespace and covers all released versions through 1.1.7, i.e. the bug is present in the shipped default code path rather than an optional mode.
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Severity by source
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
Malicious file must be locally loaded by the victim (AV:L, UI:R) with no authentication (PR:N); crash dominates impact (A:H) with limited heap-write integrity effect (I:L) and no confidentiality loss (C:N).
Primary rating from Vendor (VulnCheck).
CVSS VectorVendor: VulnCheck
DescriptionCVE.org
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.
Threat Intelligence Overview
NVD
CVE.org
EPSS
Vulnrichment
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
Memory corruption occurs when a program writes data beyond the boundaries of allocated memory regions or accesses memory in unintended ways, violating the integrity of the process's address space.
Exploit-DB