# CVE-2021-27562: Arm Trusted Firmware Out-of-Bounds Write Vulnerability

> CVE-2021-27562: Arm Trusted Firmware Out-of-Bounds Write Vulnerability. CVSS 5.5 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2021-27562
Last updated: 2025-10-21T23:25:45Z

- Published: 2021-05-25 18:27 UTC · Updated: 2025-10-21 23:25 UTC · Assigner: mitre
- CVSS: 5.5 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS: 3.1%, 88th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2021-11-03, federal due date 2021-11-17, ransomware use: Unknown

## Description

In Arm Trusted Firmware M through 1.2, the NS world may trigger a system halt, an overwrite of secure data, or the printing out of secure data when calling secure functions under the NSPE handler mode.

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- Arm: Trusted Firmware

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-27562)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2021-27562)
- [https://developer.arm.com/support/arm-security-updates](https://developer.arm.com/support/arm-security-updates)
- [https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git/tree/docs/security/security\_advisories/svc\_caller\_sp\_fetching\_vulnerability.rst](https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git/tree/docs/security/security_advisories/svc_caller_sp_fetching_vulnerability.rst)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2021-27562 · Markdown: https://rewindex.com/cve/CVE-2021-27562.md · JSON: https://rewindex.com/api/v1/cves/CVE-2021-27562 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:15:53.244Z