CVE-2021-27562
Actively exploited. CVE-2021-27562 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.
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.
CSIRTS triage
- What
- The vulnerability allows out-of-bounds write that can trigger a system halt or overwrite secure data.
- Who is affected
- Yealink Device Management servers are affected.
- Urgency
- Immediate action is required due to active exploitation and critical severity.
- Action
- Apply the latest updates for Arm Trusted Firmware.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 86% of all EPSS-scored CVEs.
Advisory coverage (1)
- criticalexploitedCVE-2021-27562: Arm Trusted Firmware Out-of-Bounds Write Vulnerabilitycisa-kev · 2021-11-03
External references
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