Vulnerability · Published Mar 18, 2026 · Assigned by GitHub_M

CVE-2026-32723SandboxJS timers have an execution-quota bypass (cross-sandbox currentTicks race)

Medium 4.8

In plain English

A medium-severity race condition in SandboxJS from nyariv. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)4.8Medium

Exploit odds (30 days)0.2%top 95.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.35, SandboxJS timers have an execution-quota bypass. A global tick state (`currentTicks.current`) is shared between sandboxes. Timer string handlers are compiled at execution time using that global tick state rather than the scheduling sandbox's tick object. In multi-tenant / concurrent sandbox scenarios, another sandbox can overwrite `currentTicks.current` between scheduling and execution, causing the timer callback to run under a different sandbox's tick budget and bypass the original sandbox's execution quota/watchdog. Version 0.8.35 fixes this issue.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	@nyariv/sandboxjs	0.8.35	GHSA-7p5m-xrh7-769r

Affected products (as reported)

Vendor	Product	Versions
nyariv	SandboxJS	< 0.8.35

Weakness: CWE-362 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

References

https://github.com/nyariv/SandboxJS/security/advisories/GHSA-7p5m-xrh7-769r x_refsource_CONFIRM
https://github.com/nyariv/SandboxJS/commit/cc8f20b4928afed5478d5ad3d1737ef2dcfaac29 x_refsource_MISC