CVE-2026-44287CWE-184CWE-94

FastGPT: sandbox escape to RCE - code-sandbox regex /\bimport\s*\(/ is bypassable

Medium · published May 29, 2026

CVSS v3.1
6.3
EPSS
0%
Percentile
35.9
In the wild
Unconfirmed
What it is

FastGPT is an AI Agent building platform. Prior to 4.15.0-beta1, the JavaScript sandbox worker at projects/code-sandbox/src/pool/worker.ts:356 blocks dynamic import() with the regex /\bimport\s*\(/.test(code). JavaScript syntax accepts a block comment between import and (; the regex matches only ASCII whitespace, and the bytes /, *, *, / are not in the \s character class. The payload import/**/("child_process") parses as a syntactically valid dynamic import that the regex does not detect. Because import() is not wrapped by the safeRequire Proxy (which only proxies require), the attacker loads child_process and calls execSync - arbitrary command execution as uid=100(sandbox) inside the sandbox container. This vulnerability is fixed in 4.15.0-beta1.

The record
Technical detail
CVSS v3.1
6.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
CVSS v4.0
Not supplied
EPSS
0.00427 · 35.9th percentile
Weaknesses
CWE-184 · Incomplete List of Disallowed Inputs; CWE-94 · Improper Control of Generation of Code ('Code Injection')
Published
2026-05-29T19:33Z
EPSS history
Timeline
  • 29 MAY 19:33Z
    FastGPT: sandbox escape to RCE - code-sandbox regex /\bimport\s*\(/ is bypassable
    cvelistv5