GHSA-43RV-JRFH-9MRR
Vulnerability from github – Published: 2026-09-27 03:31 – Updated: 2026-09-27 03:31vm2 before 3.12.2 does not apply its Buffer backing-store ownership invariant (byteOffset === 0 and buffer.byteLength === length) to Buffers returned from host builtin modules. When an application explicitly exposes Node's zlib module through NodeVM's builtin allowlist (require: { builtin: ['zlib'] }), zlib.deflateSync can return a Buffer backed by Node's shared small-buffer pool whose .buffer is the entire pool. Untrusted guest code can construct a full-width view of that ArrayBuffer (Buffer.from(result.buffer, 0, result.buffer.byteLength)) to read and modify bytes belonging to unrelated host buffers, disclosing and corrupting host-realm memory across the sandbox boundary.
{
"affected": [],
"aliases": [
"CVE-2026-100723"
],
"database_specific": {
"cwe_ids": [
"CWE-200"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-27T02:17:19Z",
"severity": "MODERATE"
},
"details": "vm2 before 3.12.2 does not apply its Buffer backing-store ownership invariant (byteOffset === 0 and buffer.byteLength === length) to Buffers returned from host builtin modules. When an application explicitly exposes Node\u0027s zlib module through NodeVM\u0027s builtin allowlist (require: { builtin: [\u0027zlib\u0027] }), zlib.deflateSync can return a Buffer backed by Node\u0027s shared small-buffer pool whose .buffer is the entire pool. Untrusted guest code can construct a full-width view of that ArrayBuffer (Buffer.from(result.buffer, 0, result.buffer.byteLength)) to read and modify bytes belonging to unrelated host buffers, disclosing and corrupting host-realm memory across the sandbox boundary.",
"id": "GHSA-43rv-jrfh-9mrr",
"modified": "2026-09-27T03:31:03Z",
"published": "2026-09-27T03:31:03Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/patriksimek/vm2/security/advisories/GHSA-489w-w794-jq94"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-100723"
},
{
"type": "WEB",
"url": "https://github.com/patriksimek/vm2/commit/4f2508abeb252aa86eb6761c78b3b000248fb089"
},
{
"type": "WEB",
"url": "https://github.com/patriksimek/vm2/commit/5214b02ef13b82497fcb917b45320dfd014ffd09"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/vm2-before-3.12.2-memory-disclosure-via-zlib-buffer-pool"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
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