How severe is CVE-2021-1789?

CVE-2021-1789 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1789 being actively exploited?

Yes. CVE-2021-1789 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-05-04, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2021-1789?

CVE-2021-1789 primarily affects Apple Ipados. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1789?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2021-1789 have an EU (EUVD) identifier?

Yes. CVE-2021-1789 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7253. It is also flagged as exploited in the EUVD (since 2022-05-04).

When was CVE-2021-1789 published?

CVE-2021-1789 was published on 2021-04-02 and last updated on 2026-06-17.

CVE-2021-1789

CVE-2021-1789 is a high-severity vulnerability in Apple Ipados with a CVSS 3.x base score of 8.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-05-04). The underlying weakness is classified as CWE-843.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 15% (96th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-05-04)
EU (EUVD) id: EUVD-2021-7253
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-05-04)
Weakness: CWE-843
Affected product: Apple Ipados
Published: 2021-04-02
Last modified: 2026-06-17

Description

A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution.

Frequently asked questions

What is CVE-2021-1789?: A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution.
How severe is CVE-2021-1789?: CVE-2021-1789 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1789 being actively exploited?: Yes. CVE-2021-1789 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-05-04, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-1789?: CVE-2021-1789 primarily affects Apple Ipados. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1789?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2021-1789 have an EU (EUVD) identifier?: Yes. CVE-2021-1789 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7253. It is also flagged as exploited in the EUVD (since 2022-05-04).
When was CVE-2021-1789 published?: CVE-2021-1789 was published on 2021-04-02 and last updated on 2026-06-17.

References

Affected products (25)

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_2019-004:*:*:*:*:*:*
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:supplemental_update:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:supplemental_update_2:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:-:*:*:*:*:*:*
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:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:a:webkitgtk:webkitgtk:*:*:*:*:*:*:*:*

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