How severe is CVE-2021-1883?

CVE-2021-1883 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-1883 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1883?

CVE-2021-1883 primarily affects Apple Ipados. In total, 35 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1883?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-1883 published?

CVE-2021-1883 was published on 2021-09-08 and last updated on 2026-06-17.

CVE-2021-1883

CVE-2021-1883 is a medium-severity vulnerability in Apple Ipados with a CVSS 3.x base score of 5.5. 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Apple Ipados
Published: 2021-09-08
Last modified: 2026-06-17

Description

This issue was addressed with improved checks. This issue is fixed in Security Update 2021-004 Mojave, iOS 14.5 and iPadOS 14.5, watchOS 7.4, Security Update 2021-003 Catalina, tvOS 14.5, macOS Big Sur 11.3. Processing maliciously crafted server messages may lead to heap corruption.

Frequently asked questions

What is CVE-2021-1883?: This issue was addressed with improved checks. This issue is fixed in Security Update 2021-004 Mojave, iOS 14.5 and iPadOS 14.5, watchOS 7.4, Security Update 2021-003 Catalina, tvOS 14.5, macOS Big Sur 11.3. Processing maliciously crafted server messages may lead to heap corruption.
How severe is CVE-2021-1883?: CVE-2021-1883 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-1883 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1883?: CVE-2021-1883 primarily affects Apple Ipados. In total, 35 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1883?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-1883 published?: CVE-2021-1883 was published on 2021-09-08 and last updated on 2026-06-17.

References

Affected products (35)

cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:-:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-004:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-005:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-006:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-007:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-003:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-004:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-005:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-006:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-007:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2021-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2021-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2021-003:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:supplemental_update:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:supplemental_update_2:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.6:-:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.6:supplemental_update:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:-:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020-005:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020-007:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:supplemental_update:*:*:*:*:*:*
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

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