---
id: CVE-2026-21085
title: >-
  Out-of-bounds write in Keymaster trustlet prior to SMR Sep-2026 Release 1
  allows local privileged attackers to write out-of-bounds memory.
summary: >-
  Out-of-bounds write in Keymaster trustlet prior to SMR Sep-2026 Release 1
  allows local privileged attackers to write out-of-bounds memory.
severity: medium
cvss: 6.7
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-787
vendor: samsung
product: android
affected:
  - android = 14.0
  - android = 15.0
  - android = 16.0
  - android = 17.0
published: '2026-09-09'
updated: '2026-09-11'
sourceUpdated: '2026-09-11T04:17:35.460'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-21085'
references:
  - url: 'https://security.samsungmobile.com/securityUpdate.smsb?year=2026&month=09'
    label: mobile.security@samsung.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-10T00:00:00+00:00'
scores:
  nvd: 6.7
  cna: 8.4
ingestedAt: '2026-09-13T04:25:52.155Z'
epss: 0.00109
epssPercentile: 0.01387
---

## Overview

Out-of-bounds write in Keymaster trustlet prior to SMR Sep-2026 Release 1 allows local privileged attackers to write out-of-bounds memory.

## Affected

- `android = 14.0`
- `android = 15.0`
- `android = 16.0`
- `android = 17.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.