What is CVE-2023-21391?

CVE-2023-21391 is a high-severity vulnerability in Google Android, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2023-10-30.

How severe is CVE-2023-21391?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2023-21391 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Improper input validation in Google Android

CVE-2023-21391

In Messaging, there is a possible way to disable the messaging application due to improper input validation. This could lead to remote denial of service with no additional execution privileges needed. User interaction is not needed for exploitation.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2023-10-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.004 (33.5th percentile), scored 2026-10-05.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Google Android — versions 14

Weakness classification (CWE)

CWE-20 — Improper Input Validation

Public proof-of-concept exploits

fkie-cad/nvd-json-data-feeds

References

source.android.com/docs/security/bulletin/android-14 (Release Notes, Vendor Advisory)

Frequently asked questions

What is CVE-2023-21391?: CVE-2023-21391 is a high-severity vulnerability in Google Android, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2023-10-30.
How severe is CVE-2023-21391?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2023-21391 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.