Bug 2541994 (CVE-2026-100722)

Summary: CVE-2026-100722 vm2: vm2: Denial of Service via unhandled Promise rejection in construct trap
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: abarbaro, alizardo, dschmidt, ikhan, jchui, jhe, jlanda, kshier, ktsao, nboldt, oaljalju, psrna, rbobbitt, simaishi, stcannon, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in vm2. An attacker who can execute untrusted code within the sandbox can trigger an unhandled error by instantiating host-provided functions that return a rejected asynchronous operation (Promise). Due to missing error handling in the sandbox-to-host object construction trap, the unhandled failure crosses into the host runtime. This condition causes the host application to terminate unexpectedly, resulting in a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-27 01:51:24 UTC 
vm2 before 3.12.2 does not apply host-side Promise rejection handling in the sandbox-to-host construct trap. In BaseHandler, the apply trap calls markHostPromiseHandled() on the returned value, but the adjacent construct path returns the result of Reflect.construct without the same sanitization. If an embedder exposes a constructable host function whose constructor returns a native rejected Promise, an untrusted script executed via VM.run can invoke it with `new` and ignore the result; the rejected host Promise crosses the bridge unhandled and, under Node's strict unhandled-rejection policy, is promoted to an uncaught exception that terminates the host process.