SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-9955

An out-of-bounds write issue was addressed with improved bounds checking.

HIGH 7.8EPSS 1.05%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.05%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in watchOS 7.0, tvOS 14.0, iOS 14.0 and iPadOS 14.0, macOS Big Sur 11.0.1. Processing a maliciously crafted image may lead to arbitrary code execution.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
1.05% probability · 64th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-787
Affected
apple/ipados · apple/iphone os · apple/macos · apple/tvos · apple/watchos
Source
product-security@apple.com
EPSS trend
0%3%5%26 October 2026: 1.05%26 October 202626 October 2026

EPSS 1.1% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.