CVE-2021-25338

EL2 memory corruption via writable RKP region list

Published Mar 4, 2021 · Updated Aug 3, 2024

Improper memory access control in Samsung Mobile Devices before SMR Mar-2021 Release 1 allows attackers to write RKP EL2 memory. RKP leaves its region list writable from EL1 instead of enforcing access controls that make the protected EL2 memory region inaccessible. Exploitation requires control of the device kernel on an affected Exynos 9830 device and permits modification of memory intended to remain isolated at EL2.

CVSS severity4.4
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper memory access control in Samsung Mobile Devices before SMR Mar-2021 Release 1 allows attackers to write RKP EL2 memory. RKP leaves its region list writable from EL1 instead of enforcing access controls that make the protected EL2 memory region inaccessible. Exploitation requires control of the device kernel on an affected Exynos 9830 device and permits modification of memory intended to remain isolated at EL2.

The record

CVE
CVE-2021-25338
Published
Mar 4, 2021
Updated
Aug 3, 2024
Vendor
Samsung Electronics Co., Ltd.
Product
Samsung Mobile Devices
Classifications
CWE-20, T1068
Attack vector
physical
Privileges
admin

Timeline

How it unfolded

  1. Mar 4, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Selected Q(10.0), R(11.0) <SMR Mar-2021 Release 1

What conditions does exploitation require?

Attack vectorphysical
Required privilegesadmin

What is affected?

Samsung Electronics Co., Ltd. · Samsung Mobile Devicesversion=Selected Q(10.0), R(11.0) <SMR Mar-2021 Release 1

Published CVSS scores

4.4Samsung MobileCVSS:3.1/AV:P/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:L
5.2NIST NVDCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L

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.

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No observations available

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

Weakness, pattern, technique

CWE-20Improper Input Validation
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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