CASCACascade Atlas

Evidence dossier

CVE-2021-27562

CVE-2021-27562

55.8–72.3Priority evidence range
As known Jul 19, 2026, 5:00 AM UTCgen-56ccdaf9

Normalized restatement

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.

State
PUBLISHED
Published
May 25, 2021
Updated
Oct 21, 2025
Evidence coverage
85%
CISA KEVCatalog member

Apply updates per vendor instructions.

FIRST EPSS3.09%

2026-07-18 · v2026.06.15 · percentile 86.3%

Source stateNo scored conflict

Distinct CVSS assessments remain side by side; none are averaged.

Source comparison

Who said what

CISA-ADPindependent enrichment
container

CISA ADP Vulnrichment

CVEderivative copy
container

CVE Program Container

mitreoriginal assertion
container

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 KEVoriginal assertion
observed_exploitation

Arm Trusted Firmware Out-of-Bounds Write Vulnerability

FIRST EPSSoriginal assertion
model_probability

Probability 0.030930000000; percentile 0.862570000000

Applicability

Cited product scope

Trace impact →
n/an/a
[{"status": "affected", "version": "n/a"}]unknown
Unknown vendorUnknown product
cpe:2.3:o:trustedfirmware:trusted_firmware-m:*:*:*:*:*:*:*:*; end including 1.2.0supported

Assessments

CVSS by origin

5.5
nvd@nist.govCVSS 3.1 · role PrimaryCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.9
nvd@nist.govCVSS 2.0 · role PrimaryAV:L/AC:L/Au:N/C:N/I:N/A:C
5.5
134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS 3.1 · role SecondaryCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5
CISA-ADPCVSS 3.1 · role unknownCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Limitations and unknowns

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
  • NVD-carried upstream facts remain derivative and are not independent corroboration.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.