How severe is CVE-2021-0956?

CVE-2021-0956 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-0956 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-0956?

CVE-2021-0956 primarily affects Google Android. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-0956?

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

When was CVE-2021-0956 published?

CVE-2021-0956 was published on 2021-12-15 and last updated on 2026-06-17.

CVE-2021-0956

CVE-2021-0956 is a critical-severity vulnerability in Google Android with a CVSS 3.x base score of 9.8. 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Google Android
Published: 2021-12-15
Last modified: 2026-06-17

Description

In NfcTag::discoverTechnologies (activation) of NfcTag.cpp, there is a possible out of bounds write due to an incorrect bounds check. This could lead to remote escalation of privilege with no additionalSystem execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11 Android-12Android ID: A-189942532

Frequently asked questions

What is CVE-2021-0956?: In NfcTag::discoverTechnologies (activation) of NfcTag.cpp, there is a possible out of bounds write due to an incorrect bounds check. This could lead to remote escalation of privilege with no additionalSystem execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11 Android-12Android ID: A-189942532
How severe is CVE-2021-0956?: CVE-2021-0956 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-0956 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-0956?: CVE-2021-0956 primarily affects Google Android. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-0956?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-0956 published?: CVE-2021-0956 was published on 2021-12-15 and last updated on 2026-06-17.

References

https://source.android.com/security/bulletin/2021-12-01

Affected products (2)

cpe:2.3:o:google:android:11.0:*:*:*:*:*:*:*
cpe:2.3:o:google:android:12.0:*:*:*:*:*:*:*

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