# CVE-2021-27561

Yealink Device Management (DM) 3.6.0.20 allows command injection as root via the /sm/api/v1/firewall/zone/services URI, without authentication.

- Page: https://www.vulneraibility.com/cve/CVE-2021-27561
- CVSS: 9.8
- Known exploited: yes, in CISA KEV since 2021-11-03; CISA due date 2021-11-17
- EPSS: 83.65% (percentile 99.7)
- Detection templates only, no public exploit found: 1 Nuclei template
- CISA SSVC: exploitation active, automatable yes, technical impact total (assessed 2025-02-04)
- Weakness: CWE-78
- Published: 2021-10-15

## Affected

- yealink:device_management

## References

- [other] https://ssd-disclosure.com/?p=4688
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27561

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.