Information Disclosure in vm2 (CVE-2026-92947)
Summary
Vulnerability in vm2 (CVE-2026-92947). Confidential information can be exposed externally. Exploitable via Buffer.from. Mitigation: upgrade to 3.11.7 or later.
Original description
The description as published by the source.
Summary
Sandboxed code is able to disclose host memory used by small allocations by Buffer.from, Buffer.concat.
Details
vm2 exposes Buffer object to sandboxed code by default. Small Buffer allocations (for example, Buffer.allocUnsafe(), Buffer.from(array), Buffer.from(string), and Buffer.concat()) use the same Buffer pool, which is shared with the sandbox. This allows sandboxed code to disclose host memory used by the functions listed above.
PoC
Tested against vm2@3.11.5 in the node REPL.
Buffer.from('host-memory-should-not-leak-to-sandbox')
new (require('vm2').VM)().run(`Buffer.from(Buffer.from([0]).buffer, 0, Buffer.from([0]).buffer.byteLength).toString('ascii')`)
Impact
Since sandbox acquires an ArrayBuffer that is used by the host, it can disclose sensitive data going through functions mentioned above and even write to these buffers, which can lead to sensitive data exposure and potentially denial-of-service.
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-2026-92947 has been found in vm2.
Attackers can target a specific entry point like Buffer.from over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 10.0/10.
What to do: upgrade vm2 to 3.11.7 or later.
If unsure, ask your IT team or search "vm2 CVE-2026-92947" on the vendor's site.
CVE-2026-92947 (vm2) — CWE-200 / CVSS v3 10.0
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: Buffer.from / Buffer.concat / Buffer
Patched: 3.11.7 — 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.
Information disclosure (CWE-200) exists in vm2. Attackers reach the vulnerable code path via Buffer.from without authentication.
Check the vendor advisory for the affected versions of vm2. Attack surface: Buffer.from / Buffer.concat / Buffer.
Severity: Critical (CVSS 10.0/10). Confidential information can be exposed externally.
Update to 3.11.7.
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 3.11.7ステージング環境で 3.11.7 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 vulncheck.com
- web github.com
- web github.com
- web github.com
- web github.com