{"cve":"CVE-2026-100723","nvd":{"published":"2026-09-27T02:17:19.373","modified":"2026-10-01T19:17:16.563","status":"Deferred","description":"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.","cvss_v4":{"vector":"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","score":6.9},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N","score":7.5},"cwes":["CWE-200"],"references":["https://github.com/patriksimek/vm2/commit/4f2508abeb252aa86eb6761c78b3b000248fb089","https://github.com/patriksimek/vm2/commit/5214b02ef13b82497fcb917b45320dfd014ffd09","https://github.com/patriksimek/vm2/security/advisories/GHSA-489w-w794-jq94","https://www.vulncheck.com/advisories/vm2-before-3.12.2-memory-disclosure-via-zlib-buffer-pool","https://github.com/patriksimek/vm2/security/advisories/GHSA-489w-w794-jq94"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:48.555445741+00:00"},"epss":{"cve":"CVE-2026-100723","score":0.00392,"percentile":0.33013,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-489w-w794-jq94","url":"https://osv.dev/vulnerability/GHSA-489w-w794-jq94","summary":"vm2: NodeVM zlib Buffers expose pooled host memory across the VM boundary","modified":"2026-10-05T23:15:04.002769867Z","packages":[{"ecosystem":"npm","name":"vm2","purl":"pkg:npm/vm2","ranges":["<3.12.2"],"fixed":["3.12.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}