CVE-2026-32128
FastGPT Python Sandbox Bypass of File-Write Restriction
FastGPT is an AI Agent building platform. In 4.14.7 and earlier, FastGPT's Python Sandbox (fastgpt-sandbox) includes guardrails intended to prevent file writes (static detection + seccomp). These guardrails are bypassable by remapping stdout (fd 1) to an arbitrary writable file descriptor using fcntl. After remapping, writing via sys.stdout.write() still satisfies the seccomp rule write(fd==1), enabling arbitrary file creation/overwrite inside the sandbox container despite the intended no file writes restriction.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
6.3
FastGPT Python Sandbox Bypass of File-Write Restriction
FastGPT is an AI Agent building platform. In 4.14.7 and earlier, FastGPT's Python Sandbox (fastgpt-sandbox) includes guardrails intended to prevent file writes (static detection + seccomp). These guardrails are bypassable by remapping stdout (fd 1) to an arbitrary writable file descriptor using fcntl. After remapping, writing via sys.stdout.write() still satisfies the seccomp rule write(fd==1), enabling arbitrary file creation/overwrite inside the sandbox container despite the intended no file writes restriction.
- Record
CVE-2026-32128- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-184
- Updated
- 2026-11-02
EUVDEUVD-2026-11408
6.3
FastGPT is an AI Agent building platform. In 4.14.7 and earlier, FastGPT's Python Sandbox (fastgpt-sandbox) includes guardrails intended to prevent file writes (static detection + seccomp). These guardrails are bypassable by remapping stdout (fd 1) to an arbitrary writable file descriptor using fcntl. After remapping, writing via sys.stdout.write() still satisfies the seccomp rule write(fd==1), enabling arbitrary file creation/overwrite inside the sandbox container despite the intended no file writes restriction.
- Record
EUVD-2026-11408- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Updated
- 2026-11-02
NVD
6.3
FastGPT is an AI Agent building platform. In 4.14.7 and earlier, FastGPT's Python Sandbox (fastgpt-sandbox) includes guardrails intended to prevent file writes (static detection + seccomp). These guardrails are bypassable by remapping stdout (fd 1) to an arbitrary writable file descriptor using fcntl. After remapping, writing via sys.stdout.write() still satisfies the seccomp rule write(fd==1), enabling arbitrary file creation/overwrite inside the sandbox container despite the intended no file writes restriction.
- Record
CVE-2026-32128- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-184
- Updated
- 2026-11-02
OSV
6.3
FastGPT Python Sandbox Bypass of File-Write Restriction
FastGPT is an AI Agent building platform. In 4.14.7 and earlier, FastGPT's Python Sandbox (fastgpt-sandbox) includes guardrails intended to prevent file writes (static detection + seccomp). These guardrails are bypassable by remapping stdout (fd 1) to an arbitrary writable file descriptor using fcntl. After remapping, writing via sys.stdout.write() still satisfies the seccomp rule write(fd==1), enabling arbitrary file creation/overwrite inside the sandbox container despite the intended no file writes restriction.
- Record
CVE-2026-32128- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-184
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | qianlijaingshan/fastgpt-sandbox-audit | 2026-08-18 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-32128 is a medium vulnerability (CVSS 6.3) in Fastgpt, published March 11, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 28th percentile. No source names a fixed version.