How severe is CVE-2023-21420?

CVE-2023-21420 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability high.

Is CVE-2023-21420 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-21420?

CVE-2023-21420 primarily affects Samsung Android. In total, 87 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-21420?

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-2023-21420 published?

CVE-2023-21420 was published on 2023-02-09 and last updated on 2026-06-17.

CVE-2023-21420

CVE-2023-21420 is a high-severity vulnerability in Samsung Android with a CVSS 3.x base score of 7.3. 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-134.

Key facts

Severity: High (CVSS 3.x base score 7.3)
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-134
Affected product: Samsung Android
Published: 2023-02-09
Last modified: 2026-06-17

Description

Use of Externally-Controlled Format String vulnerabilities in STST TA prior to SMR Jan-2023 Release 1 allows arbitrary code execution.

Frequently asked questions

What is CVE-2023-21420?: Use of Externally-Controlled Format String vulnerabilities in STST TA prior to SMR Jan-2023 Release 1 allows arbitrary code execution.
How severe is CVE-2023-21420?: CVE-2023-21420 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability high.
Is CVE-2023-21420 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-21420?: CVE-2023-21420 primarily affects Samsung Android. In total, 87 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-21420?: 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-2023-21420 published?: CVE-2023-21420 was published on 2023-02-09 and last updated on 2026-06-17.

References

https://security.samsungmobile.com/securityUpdate.smsb?year=2023&month=01

Affected products (87)

cpe:2.3:o:samsung:android:10.0:-:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-apr-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-apr-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-apr-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-apr-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-aug-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-aug-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-aug-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-aug-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-dec-2019-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-dec-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-dec-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-dec-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-dec-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-feb-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-feb-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-feb-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-feb-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jan-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jan-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jan-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jul-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jul-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jul-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jul-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jun-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jun-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jun-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-jun-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-mar-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-mar-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-mar-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-mar-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-may-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-may-2021-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-may-2022-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-may-2023-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-nov-2019-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-nov-2020-r1:*:*:*:*:*:*
cpe:2.3:o:samsung:android:10.0:smr-nov-2021-r1:*:*:*:*:*:*

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CVE-2011-1568 — Critical (CVSS 10.0): Format string vulnerability in the logText function in shmemmgr9.dll in IGSSdataServer.exe 9.00.00.11074, and…
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