Cyber Resilience

CVE-2025-66738

HighPublic PoCRCE

Published: 26 December 2025

Published
26 December 2025
Modified
09 January 2026
KEV Added
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Patch
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CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0060 43.8th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-66738 is a high-severity Command Injection (CWE-77) vulnerability in Yealink Sip-T21\(P\)E2 Firmware. Its CVSS base score is 8.8 (High).

Operationally, ranked at the 43.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

An issue in Yealink T21P_E2 Phone 52.84.0.15 allows a remote normal privileged attacker to execute arbitrary code via a crafted request the ping function of the diagnostic component.

CWE(s)
CWE-77

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

yealink
sip-t21\(p\)e2 firmware
52.84.0.15

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References