CVE-2023-21391Network attack vector

Remote Messaging disablement via improper input validation

Published Oct 30, 2023 · Updated Sep 6, 2024

Improper input validation in Android 14 Messaging allows remote attackers to disable the messaging application without user interaction. Google has not published the input field, parser, or validation failure that accepts the crafted message. No privileges or user interaction are required, and exploitation interrupts Messaging rather than the entire device.

CVSS severity7.5
High
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Android 14 Messaging allows remote attackers to disable the messaging application without user interaction. Google has not published the input field, parser, or validation failure that accepts the crafted message. No privileges or user interaction are required, and exploitation interrupts Messaging rather than the entire device.

The record

CVE
CVE-2023-21391
Published
Oct 30, 2023
Updated
Sep 6, 2024
Vendor
Google
Product
Android
Classifications
CWE-20, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 30, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 6, 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=14

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Google · Androidversion=14

Published CVSS scores

7.5NIST NVDCVSS: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.

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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.

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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