---
title: "CVE-2020-9819: Out-of-bounds Write | CubePath"
description: "A memory consumption issue was addressed with improved memory handling. This issue is fixed in iOS 13.5 and iPadOS 13.5, iOS 12.4.7, watchOS 6.2.5…"
language: en
source: https://cubepath.com/security/cve/CVE-2020-9819
---

# CVE-2020-9819: Out-of-bounds Write | CubePath

## Description

A memory consumption issue was addressed with improved memory handling. This issue is fixed in iOS 13.5 and iPadOS 13.5, iOS 12.4.7, watchOS 6.2.5, watchOS 5.3.7\. Processing a maliciously crafted mail message may lead to heap corruption.

Official description from the CVE record, published by apple. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2020-9819)

## Key data

### CVSS 3.1 Medium 4.3

Score published by CISA-ADP in the CVE record.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

| Metric                 | Value     | What it means                                                                       |
| ---------------------- | --------- | ----------------------------------------------------------------------------------- |
| Attack vector          | Network   | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity      | Low       | No special conditions are needed. The attack can be repeated at will.               |
| Privileges required    | None      | No account or privileges are needed.                                                |
| User interaction       | Required  | A user has to do something first, such as opening a file or following a link.       |
| Scope                  | Unchanged | The impact stays within the vulnerable component.                                   |
| Confidentiality impact | None      | No effect on the secrecy of data.                                                   |
| Integrity impact       | None      | No effect on the trustworthiness of data.                                           |
| Availability impact    | Low       | Limited effect on availability.                                                     |

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) .

### EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score

0.02232 (2.2% probability)

Percentile

82.9%

Scores of

Nov 10, 2026

Model

v2026.06.15

### CISA Known Exploited Vulnerabilities

This CVE is listed in the CISA KEV catalog.

Name in the catalog

Apple iOS, iPadOS, and watchOS Memory Corruption Vulnerability

Added to the catalog

Nov 3, 2021

Federal due date

May 3, 2022

### CISA assessment as of Aug 19, 2025

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.

Exploitation

Recorded by CISA as active

Automatable

no

Technical impact

total

### Weakness (CWE)

CWE catalog version 5.0.

CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license.

- [CWE-787](https://cwe.mitre.org/data/definitions/787.html) Out-of-bounds Write

## Affected products

Products listed in the CVE record, as the CNA published them.

- Apple iOS

  - affected: unspecified up to before iOS 13.5 and iPadOS 13.5
- Apple iOS-1

  - affected: unspecified up to before iOS 12.4.7
- Apple watchOS

  - affected: unspecified up to before watchOS 6.2.5
- Apple watchOS-1

  - affected: unspecified up to before watchOS 5.3.7

## References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

- [support.apple.com/HT211168](https://support.apple.com/HT211168)
- [support.apple.com/HT211175](https://support.apple.com/HT211175)
- [support.apple.com/HT211169](https://support.apple.com/HT211169)
- [support.apple.com/HT211176](https://support.apple.com/HT211176)

## Timeline

1. ID reserved Mar 2, 2020
2. Record published Jun 9, 2020
3. Added to CISA KEV Nov 3, 2021
4. Record last updated Dec 20, 2025

## Look up another CVE

## About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.

[Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection)

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:36 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)