CVE-2021-25480Network attack vector

Mobile network interruption via replayed GUTI command

Published Oct 6, 2021 · Updated Aug 3, 2024

Capture-replay weakness in Samsung Mobile Devices before SMR Oct-2021 Release 1 allows remote authenticated users to interrupt mobile connectivity. The Qualcomm modem accepts a reused GUTI REALLOCATION COMMAND after the SECURITY MODE COMMAND because the message path lacks replay protection. Exploitation requires cellular-network access sufficient to resend a previously valid control message, and the documented consequence is loss of the target device's mobile-network connection.

CVSS severity4.4
Medium
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Capture-replay weakness in Samsung Mobile Devices before SMR Oct-2021 Release 1 allows remote authenticated users to interrupt mobile connectivity. The Qualcomm modem accepts a reused GUTI REALLOCATION COMMAND after the SECURITY MODE COMMAND because the message path lacks replay protection. Exploitation requires cellular-network access sufficient to resend a previously valid control message, and the documented consequence is loss of the target device's mobile-network connection.

The record

CVE
CVE-2021-25480
Published
Oct 6, 2021
Updated
Aug 3, 2024
Vendor
Samsung Electronics Co., Ltd.
Product
Samsung Mobile Devices
Classifications
CWE-294, T1464
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 6, 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=O(8.1), P(9.0), Q(10.0), R(11.0) <SMR Oct-2021 Release 1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Samsung Electronics Co., Ltd. · Samsung Mobile Devicesversion=O(8.1), P(9.0), Q(10.0), R(11.0) <SMR Oct-2021 Release 1

Published CVSS scores

4.4Samsung MobileCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
5.0NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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

Weakness, pattern, technique

CWE-294Authentication Bypass by Capture-replay
T1464Network Denial of Service

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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