Answer in brief
CVE-2026-100723 records a Medium severity (CVSS 6.9) vulnerability in vm2 before 3.12.2 Memory Disclosure via zlib Buffer Pool. The current sources do not mark it as known exploited. The current feed maps patriksimek/vm2 (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps patriksimek/vm2 (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| patriksimek/vm2generic | >=0 <3.12.2 | 3.12.2 |
Published upstream
Sep 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 27, 2026
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.
Quoted source text, attributed separately from HOL analysis.