CVE-2026-43898 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-43898CRITICAL

nyariv SandboxJS — SandboxJS: Sandbox escape via Function.caller leakage of internal call op

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  C  H  H  H   10.0   .0047   39.0     —

AFFECTED
  Product    Versions   Fixed
  SandboxJS  < 0.9.6 –  —

TIMELINE
  May 4   Reserved by GitHub_M
  May 28  EXPLOIT PUBLISHED — CVE-2026-43898 (nyariv SandboxJS). Public exploit reference added.
  May 28  Published (CNA: GitHub_M)

CWE-94 · CNA: GitHub_M · CVSS v3.1 · 2 references · NVD status: Modified

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

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
May 4, 2026	Reserved	Reserved by GitHub_M
May 28, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-43898 (nyariv SandboxJS). Public exploit reference added.
May 28, 2026	Published	Published (CNA: GitHub_M)

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
nyariv	SandboxJS	—	< 0.9.6	—

Weaknesses

CWE-94

References (2)

https://github.com/nyariv/SandboxJS/commit/826865251232611ec94078bab5a18ec875dad4a5 [Patch]
https://github.com/nyariv/SandboxJS/security/advisories/GHSA-g8f2-4f4f-5jqw [Exploit, Vendor Advisory]

Authoritative record: CVE-2026-43898 at cve.org

Vendors: nyariv

Weaknesses: CWE-94

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-43898 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.