Bug 2536060 (CVE-2026-92949)

Summary: CVE-2026-92949 vm2: vm2: Sandbox bypass allows unauthorized data modification.
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, jchui, jhe, jlanda, kshier, ktsao, nboldt, oaljalju, psrna, simaishi, stcannon, teagle, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in vm2, a JavaScript sandbox. This vulnerability allows sandboxed scripts to bypass security protections, specifically `vm.freeze()` and `vm.readonly()`, which are designed to prevent unauthorized modifications to objects. An attacker can exploit this by directly accessing and invoking setters for properties intended to be read-only, leading to unauthorized data modification within the sandbox environment.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-09-17 14:11:45 UTC 
vm2 versions from 3.9.6 before 3.11.7 fail to properly restrict access to accessor properties on frozen objects, allowing sandboxed scripts to bypass vm.freeze() and vm.readonly() protections. Attackers can use Object.getOwnPropertyDescriptor() or __lookupSetter__() to extract and invoke host object setters directly, mutating properties the embedder explicitly marked read-only.