CVE-2026-21046

Privileged local code execution via fabricKeymaster race

Published Jul 10, 2026 · Updated Jul 10, 2026

TOCTOU race in Samsung Mobile Devices before SMR Jul-2026 Release 1 allows local privileged attackers to execute arbitrary code. Samsung identifies the fabricKeymaster trustlet and says its patch adds validation logic, but does not disclose the raced resource or operation. Exploitation requires privileged local access, and a successful race executes attacker-controlled code on the affected mobile device.

CVSS severity8.4
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

TOCTOU race in Samsung Mobile Devices before SMR Jul-2026 Release 1 allows local privileged attackers to execute arbitrary code. Samsung identifies the fabricKeymaster trustlet and says its patch adds validation logic, but does not disclose the raced resource or operation. Exploitation requires privileged local access, and a successful race executes attacker-controlled code on the affected mobile device.

The record

CVE
CVE-2026-21046
Published
Jul 10, 2026
Updated
Jul 10, 2026
Vendor
Samsung Electronics Co., Ltd.
Product
Samsung Mobile Devices
Classifications
CWE-367, T1658
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Jul 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Samsung Electronics Co., Ltd. · Samsung Mobile DevicesAffected versions are unavailable in this record.

Published CVSS scores

8.4Samsung MobileCVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
T1658Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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