JavaScript Sandboxing Library Vulnerability in SandboxJS by Nyariv
CVE-2026-34211

6.9MEDIUM

Key Information:

Vendor

Nyariv

Status
Sandboxjs
Vendor
CVE Published:
6 April 2026

What is CVE-2026-34211?

SandboxJS, a JavaScript sandboxing library developed by Nyariv, contains a vulnerability in the parser's restOfExp function and its lispify call chain prior to version 0.8.36. This flaw allows an attacker to induce unbounded recursion through the input of deeply nested expressions, potentially leading to a RangeError: Maximum call stack size exceeded in any Node.js process using the library. The result of this exploit is a crash of the affected process, which poses significant risks in production environments that rely on SandboxJS for executing untrusted JavaScript code.

Affected Version(s)

SandboxJS < 0.8.36

References

https://github.com/nyariv/SandboxJS/security/advisories/G...
x_refsource_CONFIRM

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.