CVE-2021-27562Actively exploitedAdded to KEV 2021-11-03

Arm Trusted Firmware Out-of-Bounds Write Vulnerability

Arm, Trusted Firmware

Description

Arm Trusted Firmware contains an out-of-bounds write vulnerability allowing the non-secure (NS) world to trigger a system halt, overwrite secure data, or print out secure data when calling secure functions under the non-secure processing environment (NSPE) handler mode. This vulnerability affects Yealink Device Management servers.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Medium

3.1%

estimated chance of real-world exploitation in the next 30 days, higher than 87.5% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2021-11-17

CWE-787

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