CVE-2026-34211

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

HIGH
7.5
CVSS Score
Published: April 6, 2026 at 03:10 PM UTC
Updated: October 26, 2026 at 10:10 PM UTC
1 product affected across 1 vendorSandboxJS

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Severity
HIGH7.5
Exploit prediction
EPSS 0.4%
SSVC
PoC

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.8.36
Affected range stops below 0.8.36, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/nyariv/SandboxJS/security/advisories/GHSA-8pfc-jjgw-6g26

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-674

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