CVE-2026-93603: vm2 through 3.12.0 (fixed in 3.12.1) does not correctly handle a nullish `this` receiver in the apply trap of its bridge (lib/bridge.js): when sandboxed code…

PriorityP266critical10CVSS 3.1

AVNACLPRNUINSCCHIHAH

EPSS

0.73%

52.2th percentile

vm2 through 3.12.0 (fixed in 3.12.1) does not correctly handle a nullish `this` receiver in the apply trap of its bridge (lib/bridge.js): when sandboxed code calls a host-provided non-strict (sloppy-mode) function without a receiver — e.g. `fn()`, a detached method, `fn.call()`, `fn.apply(undefined)`, `Reflect.apply(fn, undefined, [])`, or `fn.bind()()` — the undefined receiver is passed straight through to the host call, and V8 substitutes the host realm's global object for `this`. vm2 then wraps and returns that object to the sandbox, giving sandboxed script a live proxy of the host global. This allows a complete sandbox escape: untrusted script can reach `process` and execute arbitrary code/commands on the host (for example via `process.getBuiltinModule('child_process').execSync`). Exploitation requires that the embedding application expose at least one non-strict host function to the sandbox; strict-mode and ES module host functions are not affected.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
ansible-automation-platform	automation-portal	—	—
ansible-automation-platform	bootc-automation-portal-rhel9	—	—
patriksimek	vm2	< 3.12.1	3.12.1
rhdh	red-hat-developer-hub-backstage-plugin-lightspeed-backend	—	—
rhdh	red-hat-developer-hub-backstage-plugin-orchestrator-backend	—	—
rhdh	rhdh-hub-rhel9	—	—

CVSS provenance

nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

nvdv4.010.0CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

vendor_redhat10.0CRITICAL

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