{"id":"CVE-2026-100723","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-100723","summary":"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…","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'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.","published":"2026-09-27T02:17:19.373","modified":"2026-09-27T02:17:20.553","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/patriksimek/vm2/commit/4f2508abeb252aa86eb6761c78b3b000248fb089","label":"patriksimek/vm2@4f2508a"},"references":[{"type":"WEB","url":"https://github.com/patriksimek/vm2/commit/4f2508abeb252aa86eb6761c78b3b000248fb089"},{"type":"WEB","url":"https://github.com/patriksimek/vm2/commit/5214b02ef13b82497fcb917b45320dfd014ffd09"},{"type":"WEB","url":"https://github.com/patriksimek/vm2/security/advisories/GHSA-489w-w794-jq94"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/vm2-before-3.12.2-memory-disclosure-via-zlib-buffer-pool"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-09-27T02:17:20.553"}}