CVE-2020-9818An out-of-bounds write issue was addressed with improved bounds checking.
Updated under an hour ago ()
Does this affect you?
It affects Apple iOS and 4 other products. Add what you run to find out whether that includes you.
CISA lists it as known exploited since Nov 3, 2021; federal agencies had to remediate by May 3, 2022. Treat that date as your deadline.
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Free account, 1 product
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.
- CVSS
- 8.8 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-787
- Known exploited
- Added to CISA KEV Nov 3, 2021; federal remediation due May 3, 2022Apply updates per vendor instructions.
- EPSS (exploitation in the next 30 days)
- 2.29% (percentile 83)
- Assigned by
- apple
- NVD analysis
- Analyzed
- Record last updated
- Dec 20, 2025
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Apple iOS apple:ios (from the name) | from unspecified before iOS 13.5 and iPadOS 13.5 | CNA record |
Apple iOS-1 apple:ios_1 (from the name) | from unspecified before iOS 12.4.7 | CNA record |
Apple watchOS apple:watchos (from the name) | from unspecified before watchOS 6.2.5 | CNA record |
apple ipados apple:ipados | before 13.5 | NVD |
apple iphone_os apple:iphone_os | before 12.4.7; from 13.0 before 13.5 | NVD |
apple watchos apple:watchos | before 6.2.5 | NVD |
References
- https://support.apple.com/HT211168x-refsource-misc, release-notes, vendor-advisory
- https://support.apple.com/HT211175x-refsource-misc, release-notes, vendor-advisory
- https://support.apple.com/HT211169x-refsource-misc, release-notes, vendor-advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-9818us-government-resource
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.