How severe is CVE-2023-21391?

CVE-2023-21391 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-21391 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-21391?

CVE-2023-21391 affects Google Android. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-21391?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-21391 published?

CVE-2023-21391 was published on 2023-10-30 and last updated on 2026-06-17.

CVE-2023-21391

CVE-2023-21391 is a high-severity vulnerability in Google Android with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Google Android
Published: 2023-10-30
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2023-21391?: CVE-2023-21391 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-21391 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-21391?: CVE-2023-21391 affects Google Android. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-21391?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-21391 published?: CVE-2023-21391 was published on 2023-10-30 and last updated on 2026-06-17.

References

https://source.android.com/docs/security/bulletin/android-14

Affected products (1)

cpe:2.3:o:google:android:*:*:*:*:*:*:*:*

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