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TI-2026-26506 Aliases CVE-2026-34211GHSA-8pfc-jjgw-6g26

SandboxJS: Stack overflow DoS via deeply nested expressions in recursive descent parser

Priority HIGH 70CWE-674Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-674.

Summary

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.36, the @nyariv/sandboxjs parser contains unbounded recursion in the restOfExp function and the lispify/lispifyExpr call chain. An attacker can crash any Node.js process that parses untrusted input by supplying deeply nested expressions (e.g., ~2000 nested parentheses), causing a RangeError: Maximum call stack size exceeded that terminates the process. This vulnerability is fixed in 0.8.36.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0041 35th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed SandboxJS (nyariv): 0.8.36@nyariv/sandboxjs (npm): 0.8.36

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
nyarivSandboxJSbefore 0.8.360.8.36Patch availableCNA
—@nyariv/sandboxjs (npm)before 0.8.360.8.36Patch availableGHSA-8pfc-jjgw-6g26
  • SandboxJS Vendornyariv Affected before 0.8.36 Fixed in 0.8.36 Patch available CNA
  • @nyariv/sandboxjs (npm) Vendor— Affected before 0.8.36 Fixed in 0.8.36 Patch available GHSA-8pfc-jjgw-6g26

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nyariv:sandboxjs:*:*:*:*:*:node.js:*:*before 0.8.36Vulnerablenyariv
  • cpe:2.3:a:nyariv:sandboxjs:*:*:*:*:*:node.js:*:* Versions before 0.8.36 Vulnerable ·nyariv

Remediation

  • Fix · CNA SandboxJS (nyariv) Fixed in 0.8.36
  • Fix · GHSA-8pfc-jjgw-6g26 @nyariv/sandboxjs (npm) Fixed in 0.8.36 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-34211
  2. 2026-10-03 Alias added: GHSA-8pfc-jjgw-6g26

References

  • TI-2026-31962 SandboxJS: Sandbox escape via Function.caller leakage of internal call op CVSS 3.1CRITICAL 10.0
  • TI-2026-26503 SandboxJS: Sandbox integrity escape CVSS 3.1CRITICAL 10.0
  • TI-2026-21440 SandboxJS has a Sandbox Escape CVSS 3.1CRITICAL 10.0
  • TI-2026-20741 SandboxJS has a sandbox escape via TOCTOU bug on keys in property accesses CVSS 3.1CRITICAL 10.0
  • TI-2026-20694 SandboxJS has a Sandbox Escape CVSS 3.1CRITICAL 10.0
  • TI-2026-20693 SandboxJS has a Sandbox Escape via Prototype Whitelist Bypass and Host Prototype Pollution CVSS 3.1CRITICAL 10.0
See all 12 →

Sources