PT-2021-18855 · Apple · Apple Macos+4

Mickey Jin + 1 · Published 2021-05-24 · Updated 2022-03-25 · CVE-2021-30771

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

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

Name of the Vulnerable Software and Affected Versions macOS versions prior to 11.4 iOS versions prior to 14.6 iPadOS versions prior to 14.6 watchOS versions prior to 7.5 tvOS versions prior to 14.6

Description An out-of-bounds write issue was addressed with improved input validation. Processing a maliciously crafted font file may lead to arbitrary code execution.

Recommendations For macOS versions prior to 11.4, update to macOS Big Sur 11.4 to resolve the issue. For iOS versions prior to 14.6, update to iOS 14.6 to resolve the issue. For iPadOS versions prior to 14.6, update to iPadOS 14.6 to resolve the issue. For watchOS versions prior to 7.5, update to watchOS 7.5 to resolve the issue. For tvOS versions prior to 14.6, update to tvOS 14.6 to resolve the issue. As a temporary workaround, consider restricting the use of font files from untrusted sources until a patch is available.

Fix

Memory Corruption

Weakness Enumeration

CWE-787

Related Identifiers

CVE-2021-30771

ZDI-22-377

Affected Products

Apple Macos

Ios

Ipados

Tvos

Watchos

References · 10

• https://support.apple.com/en-us/HT212528 · Vendor Advisory
• https://zerodayinitiative.com/advisories/ZDI-22-377 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-30771 · Security Note
• https://osv.dev/vulnerability/CVE-2021-30771 · Vendor Advisory
• https://support.apple.com/en-us/HT212529 · Vendor Advisory
• https://support.apple.com/en-us/HT212532 · Vendor Advisory
• https://support.apple.com/en-us/HT212533 · Vendor Advisory
• https://t.me/cibsecurity/39224 · Telegram Post
• https://support.apple.com/en-us/103131 · Note
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-30771 · Note