Back
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,…
High8.8Known exploitedEPSS 2.3%
- Published
- Updated
- Reserved
- Assigned by
- apple
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.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as Apple iOS, iPadOS, and watchOS Out-of-Bounds Write Vulnerability.
- Added
- 3 Nov 2021
- Fix due (US federal)
- 3 May 2022
- Used by ransomware
- Not known
Apply updates per vendor instructions.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 2.3% · top 16% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: no · Technical impact: total
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Weakness
- Processing a maliciously crafted mail message may lead to unexpected memory modification or application termination
- CWE-787 Out-of-bounds Write (opens in a new tab)All about CWE-787 and its CVEs
Affected products
References (4)
- https://support.apple.com/HT211168 (opens in a new tab)x_refsource_MISCx_transferred
- https://support.apple.com/HT211175 (opens in a new tab)x_refsource_MISCx_transferred
- https://support.apple.com/HT211169 (opens in a new tab)x_refsource_MISCx_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-9818 (opens in a new tab)government-resource
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-9818)Record last updated .