{"id":"CVE-2026-25586","aliases":["GHSA-jjpw-65fv-8g48"],"url":"https://o3.security/vulnerability/CVE-2026-25586","summary":"SandboxJS has a Sandbox Escape via Prototype Whitelist Bypass and Host Prototype Pollution","details":"SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, a sandbox escape is possible by shadowing hasOwnProperty on a sandbox object, which disables prototype whitelist enforcement in the property-access path. This permits direct access to __proto__ and other blocked prototype properties, enabling host Object.prototype pollution and persistent cross-sandbox impact. This vulnerability is fixed in 0.8.29.","published":"2026-02-06T19:54:38.446Z","modified":"2026-07-15T01:48:58.746545125Z","cvss":{"score":10,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@nyariv/sandboxjs","fixedVersion":"0.8.29"}],"fix":{"url":"https://github.com/nyariv/SandboxJS/commit/67cb186c41c78c51464f70405504e8ef0a6e43c3","label":"nyariv/SandboxJS@67cb186"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25586.json"},{"type":"ADVISORY","url":"https://github.com/nyariv/SandboxJS/security/advisories/GHSA-jjpw-65fv-8g48"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-25586"},{"type":"FIX","url":"https://github.com/nyariv/SandboxJS/commit/67cb186c41c78c51464f70405504e8ef0a6e43c3"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-15T01:48:58.746545125Z"}}