Vulnerability in vm2 (CVE-2026-44003)
Summary
Vulnerability in vm2 (CVE-2026-44003). Risk of unauthorized operations or information disclosure. Exploitable via catch. Mitigation: upgrade to 3.11.0 or later.
Original description
The description as published by the source.
Summary
vm2's code transformer has a performance optimization that skips AST analysis when the code does not contain catch, import, or async keywords. This fast-path bypass allows sandboxed code to directly access the internal VM2_INTERNAL_STATE_DO_NOT_USE_OR_PROGRAM_WILL_FAIL variable, which exposes internal security functions (handleException, wrapWith, import).
Details
In lib/transformer.js:55-57, a regex check /\b(?:catch|import|async)\b/ determines whether AST transformation is needed. If the code does not contain any of these keywords, the transformer returns the code unmodified.
When the fast-path is taken:
- INTERNAL_STATE_NAME identifier check is bypassed: The AST visitor that blocks access to
VM2_INTERNAL_STATE_DO_NOT_USE_OR_PROGRAM_WILL_FAILnever runs withstatement instrumentation is bypassed:with()statements are not wrapped withwrapWith(), enabling scope manipulation- The internal state object exposes:
handleException(e),wrapWith(x),import(what)
While these methods are currently defensive utilities (not direct escape vectors), this represents a complete bypass of a security control. Any future addition of a sensitive method to the internal state object would be immediately exploitable.
PoC
Library-level PoC (Node.js script — primary):
const { VM } = require("vm2");
const vm = new VM();
// Access internal state (bypassed — no catch/import/async keywords)
const result = vm.run(`…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-44003 has been found in vm2.
Attackers can target a specific entry point like catch over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: upgrade vm2 to 3.11.0 or later.
If unsure, ask your IT team or search "vm2 CVE-2026-44003" on the vendor's site.
CVE-2026-44003 (vm2) — CWE-693 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: catch / import / async / handleException
Patched: 3.11.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-693) exists in vm2. Attackers reach the vulnerable code path via catch without authentication.
Check the vendor advisory for the affected versions of vm2. Attack surface: catch / import / async / handleException.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to 3.11.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'vm2' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'vm2' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
vm2を grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade vm2 to 3.11.0ステージング環境で 3.11.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web github.com