What is CVE-2026-43898?

CVE-2026-43898 is a critical-severity vulnerability in Nyariv Sandboxjs, classified under Code Injection. CVSS score: 10.0/10. Published 2026-05-28.

How severe is CVE-2026-43898?

Critical severity. CVSS v3 base score is 10.0 out of 10.

RCE in Nyariv Sandboxjs

CVE-2026-43898

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…

Vulnerability class: RCE (Remote Code Execution)

EPSS: 0.001 (19.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

Affected products

Nyariv Sandboxjs — versions < 0.9.6

Weakness classification (CWE)

CWE-94 — Code Injection

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2026-43898?: CVE-2026-43898 is a critical-severity vulnerability in Nyariv Sandboxjs, classified under Code Injection. CVSS score: 10.0/10. Published 2026-05-28.
How severe is CVE-2026-43898?: Critical severity. CVSS v3 base score is 10.0 out of 10.