CVE-2023-21504Network attack vector

Baseband memory corruption via unchecked coordination input

Published May 4, 2023 · Updated Feb 12, 2025

Buffer overflow in Samsung Mobile Devices before SMR May-2023 Release 1 allows remote attackers to cause invalid memory access. The mm_Plmncoordination.c code in the Shannon baseband fails to validate untrusted coordination input before accessing memory. Affected devices must use an Exynos CP chipset; published material establishes memory corruption but not code execution.

CVSS severity9.8
Critical
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in Samsung Mobile Devices before SMR May-2023 Release 1 allows remote attackers to cause invalid memory access. The mm_Plmncoordination.c code in the Shannon baseband fails to validate untrusted coordination input before accessing memory. Affected devices must use an Exynos CP chipset; published material establishes memory corruption but not code execution.

The record

CVE
CVE-2023-21504
Published
May 4, 2023
Updated
Feb 12, 2025
Vendor
Samsung Electronics Co., Ltd.
Product
Samsung Mobile Devices
Classifications
CWE-20, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 4, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 12, 2025Record 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=Select devices using Exynos CP chipsets <SMR May-2023 Release 1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Samsung Electronics Co., Ltd. · Samsung Mobile Devicesversion=Select devices using Exynos CP chipsets <SMR May-2023 Release 1

Published CVSS scores

5.6Samsung MobileCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499.004Application or System Exploitation

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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