4.3

CVE-2020-9819: Apple iOS, iPadOS, and watchOS Memory Corruption Vulnerability

CVSS: 4.3v3.1MediumKEVAnalyzed
Published 09-06-2020Last modified 20-12-2025
Open JSON

Vulnerability summary

CVE-2020-9819 is a medium (CVSS 4.3) Out-of-bounds Write vulnerability in Apple iOS, iPadOS, and watchOS. It is known to be exploited: CISA lists it, first on 03-11-2021. EPSS estimates a 2.18% chance of exploitation in the next 30 days, higher than 82.1% of scored vulnerabilities.

Overall risk
85/100
0100
Critical · default modelHow is this calculated?
CVSS score
4.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
2.18%
0%100%
Low · 0.00 pp in 30 days
KEVListedCISA
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 09-06-2020
    PublishedVulnerability first disclosed.
  2. 03-11-2021
    Added to CISA KEVApple iOS, iPadOS, and watchOS Memory Corruption Vulnerability
  3. 03-05-2022
    CISA remediation dueApply updates per vendor instructions.
  4. 20-12-2025
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

2.18%

Chance of exploitation in the next 30 days

Percentile

82%

Versus all other CVEs

30-day change

0.00 pp

From 2.18% on 21-09-2026

21-09-202621-10-2026
EPSS score
2.18%

Known exploited

Compare KEV catalogs
CISA KEVListed
Added
03-11-2021
Federal due date
03-05-2022

CISA required action

Apply updates per vendor instructions. nvd.nist.gov/vuln/detail/CVE-2020-9819

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Apple6 products
  • ios≥ unspecified, < iOS 13.5 and iPadOS 13.5
  • ios-1≥ unspecified, < iOS 12.4.7
  • ipados< 13.5
  • iphone_os< 12.4.7 | ≥ 13.0, < 13.5
  • watchos≥ unspecified, < watchOS 6.2.5 | < 5.3.7 | ≥ 6.0.0, < 6.2.5

1 vendor · 6 products

References

5 links