CVE-2021-27562: Arm Trusted Firmware Out-of-Bounds Write Vulnerability
Vulnerability summary
CVE-2021-27562 is a medium (CVSS 5.5) Out-of-bounds Write vulnerability in Arm Trusted Firmware. It is known to be exploited: CISA lists it, first on 03-11-2021. EPSS estimates a 3.06% chance of exploitation in the next 30 days, higher than 87.4% of scored vulnerabilities.
Timeline
- 25-05-2021PublishedVulnerability first disclosed.
- 03-11-2021Added to CISA KEVArm Trusted Firmware Out-of-Bounds Write Vulnerability
- 17-11-2021CISA remediation dueApply updates per vendor instructions.
- 21-10-2025Last modifiedVulnerability information updated.
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.
CVSS metrics
3 scores · 2 sources · 2 versions- NVDNIST5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
3.06%
Chance of exploitation in the next 30 days
Percentile
87%
Versus all other CVEs
30-day change
-0.03 pp
From 3.09% on 20-09-2026
Known exploited
Compare KEV catalogs
CISA KEVListed- Added
- 03-11-2021
- Federal due date
- 17-11-2021
CISA required action
Apply updates per vendor instructions. nvd.nist.gov/vuln/detail/CVE-2021-27562
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Trustedfirmware1 product
- trusted_firmware-m≤ 1.2.0
1 vendor · 1 product
References
3 links- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27562Government ResourceUS Government Resource