Skip to content
CVE PROGRAM SOURCE RECORD10.0 Critical

CVE-2026-25641

SandboxJS has a sandbox escape via TOCTOU bug on keys in property accesses

Description

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, there is a sandbox escape vulnerability due to a mismatch between the key on which the validation is performed and the key used for accessing properties. Even though the key used in property accesses is annotated as string, this is never enforced. So, attackers can pass malicious objects that coerce to different string values when used, e.g., one for the time the key is sanitized using hasOwnProperty(key) and a different one for when the key is used for the actual property access. This vulnerability is fixed in 0.8.29.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

nyariv SandboxJS

  • < 0.8.29affected

References