Cyber Posture

CVE-2026-43898

CriticalPublic PoCRCE

Published: 28 May 2026

Published
28 May 2026
Modified
28 May 2026
KEV Added
Patch
CVSS Score 10.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score N/A
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-43898 is a critical-severity Code Injection (CWE-94) vulnerability in Nyariv Sandboxjs. Its CVSS base score is 10.0 (Critical).

Operationally, it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Threat & Defense Details

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-94

Makes persistent code injection into loaded programs impossible when the executable image itself resides on hardware-protected read-only media.

addresses: CWE-94

Dynamically generated code can be produced and executed inside the isolated chamber, preventing host compromise from code-injection payloads.

addresses: CWE-94

Validates inputs used in dynamic code generation to block injected directives.

addresses: CWE-94

Directly prevents execution of attacker-supplied code written into data memory regions.

NVD Description

SandboxJS is a JavaScript sandboxing library. Prior to 0.9.6, sandbox-defined functions expose Function.caller, allowing sandboxed code to recover the internal LispType.Call runtime callback. That callback can then be invoked with attacker-controlled fake context and obj values to extract blocked host…

more

statics, recover the real host Function constructor, and execute arbitrary host JavaScript. This vulnerability is fixed in 0.9.6.

Deeper analysisAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)
OWASP Top 10 Web 2025

Affected Products

nyariv
sandboxjs
≤ 0.9.6

EU & UK References

Regulatory context (EU CRA / NIS2 / DORA / UK NIS Regulations)

EU Cyber Resilience Act — coordinated disclosure

Critical and high-severity vulnerabilities in products with digital elements may trigger coordinated-disclosure obligations under the EU Cyber Resilience Act (CRA, Regulation 2024/2847). Manufacturers placing products on the EU market must notify ENISA and the relevant CSIRTs without undue delay once active exploitation is known.

References