CVE-2020-27904

HIGH

macOS Big Sur <11.0.1 - Memory Corruption

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2020-27904. PoCs published by pattern-f.

AI-analyzed exploit summary This repository contains a proof-of-concept exploit for CVE-2020-27904, a macOS kernel vulnerability in extended file attributes (xattr) that allows for out-of-bounds memory access, leading to a tfp0 (task-for-pid-zero) exploit on macOS 10.15.x and below. The exploit leverages AppleDouble headers and xattr manipulation to achieve kernel memory corruption.

Description

A logic issue existed resulting in memory corruption. This was addressed with improved state management. This issue is fixed in macOS Big Sur 11.0.1. An application may be able to execute arbitrary code with kernel privileges.

Exploits (1)

nomisec WORKING POC 68 stars
by pattern-f · poc
https://github.com/pattern-f/xattr-oob-swap

This repository contains a proof-of-concept exploit for CVE-2020-27904, a macOS kernel vulnerability in extended file attributes (xattr) that allows for out-of-bounds memory access, leading to a tfp0 (task-for-pid-zero) exploit on macOS 10.15.x and below. The exploit leverages AppleDouble headers and xattr manipulation to achieve kernel memory corruption.

Classification
Working Poc 90%
Attack Type
Lpe
Complexity
Complex
Reliability
Reliable
Target: macOS 10.15.x and below
No auth needed
Prerequisites: macOS 10.15.x or below · Local access to the target system
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (4)

Core 4
Core References
Vendor Advisory x_refsource_misc
https://support.apple.com/en-us/HT211931
Mailing List, Third Party Advisory mailing-list x_refsource_fulldisc
http://seclists.org/fulldisclosure/2020/Dec/32
Vendor Advisory x_refsource_confirm
https://support.apple.com/kb/HT212147
Mailing List, Third Party Advisory mailing-list x_refsource_fulldisc
http://seclists.org/fulldisclosure/2021/Feb/14

Scores

CVSS v3 7.8
EPSS 0.0530
EPSS Percentile 90.1%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

Status published
Products (1)
apple/macos < 11.0.1
Published Dec 08, 2020
Tracked Since Feb 18, 2026