How severe is CVE-2020-9818?

CVE-2020-9818 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-2020-9818 being actively exploited?

Yes. CVE-2020-9818 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2020-9818?

CVE-2020-9818 primarily affects Apple Ipados. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-9818?

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-2020-9818 have an EU (EUVD) identifier?

Yes. CVE-2020-9818 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-30597. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2020-9818 published?

CVE-2020-9818 was published on 2020-06-09 and last updated on 2026-06-17.

CVE-2020-9818

CVE-2020-9818 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 2021-11-03). The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2020-30597
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-787
Affected product: Apple Ipados
Published: 2020-06-09
Last modified: 2026-06-17

Description

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.5 and iPadOS 13.5, iOS 12.4.7, watchOS 6.2.5. Processing a maliciously crafted mail message may lead to unexpected memory modification or application termination.

Frequently asked questions

What is CVE-2020-9818?: An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.5 and iPadOS 13.5, iOS 12.4.7, watchOS 6.2.5. Processing a maliciously crafted mail message may lead to unexpected memory modification or application termination.
How severe is CVE-2020-9818?: CVE-2020-9818 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-2020-9818 being actively exploited?: Yes. CVE-2020-9818 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2020-9818?: CVE-2020-9818 primarily affects Apple Ipados. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-9818?: 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-2020-9818 have an EU (EUVD) identifier?: Yes. CVE-2020-9818 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-30597. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2020-9818 published?: CVE-2020-9818 was published on 2020-06-09 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

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