vm2 is a widely used Node.js sandbox; this bug allows full sandbox escape and arbitrary host RCE in any app embedding vm2, posing broad enterprise impact.
CVE-2026-93603
vm2 sandbox escape → host RCE via non-strict host functions (fixed in 3.12.1).
do firstUpgrade to a fixed release: 3.12.1.
Is CVE-2026-93603 being exploited?
Not confirmed. CVE-2026-93603 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.73% probability of exploitation in the next 30 days.
How severe is CVE-2026-93603?
CVE-2026-93603 is rated Critical with a CVSS score of 10.0. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-93603?
Yes. A fix has been recorded for CVE-2026-93603. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-93603 affect?
CVE-2026-93603 affects vm2 <= 3.12.0, Node.js applications embedding vm2, Apps exposing non-strict host functions to vm2. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-93603?
Upgrade vm2 to >= 3.12.1 and audit/remove non-strict host functions exposed to sandboxes.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Sandbox escape to host: attacker can obtain host global, access process, load child_process and execute arbitrary commands (RCE).
Immediate action required
- affected< 3.12.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
cisa ssvc
- exploitation
- poc
- automatable
- yes
- technical impact
- total
Assessed by CISA 22 Sept 2026 (SSVC 2.0.3).
timeline
- 18 Sept 2026Published
- 20 Sept 2026Analysed by vulneraibility.com · 2 days later
- 22 Sept 2026CISA SSVC assessment: exploitation poc · 2 days later
- 22 Sept 2026CVE record last updated · same day later
also known as
- Advisorygithub.com /patriksimek/vm2/security/advisories/GHSA-j89j-5m6r-cr2q
- Advisoryvulncheck.com /advisories/vm2-before-3.12.1-sandbox-escape-rce-via-non-strict-host-function
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- OSV: advisory aliases and downstream package versions
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.