# CVE-2020-9771 — Apple macOS

> As of 2024-08-04, CVE-2020-9771 is a vulnerability in Apple macOS, EPSS 0.3% (29.2th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2020-9771, most recently “AmnesiaStealer: macOS Infostealer Hijacks Live Browser Sessions via Chrome DevTools Protocol Remote Control”.

**Last updated:** 2024-08-04

## What is CVE-2020-9771?

This issue was addressed with a new entitlement. This issue is fixed in macOS Catalina 10.15.4. A user may gain access to protected parts of the file system.

1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 2192 days ago.

## Severity and exploitation probability

- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 29.2% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 3.2/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2020-10-22, last modified 2024-08-04

## Is CVE-2020-9771 being exploited?

Weaponised exploit code for CVE-2020-9771 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 20 in the Threadlinqs vulnerability feed.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2020/CVE-2020-9771.md) (trickest)

## Affected products and versions

- [Apple](https://intel.threadlinqs.com/vendors/apple): macOS

## How to fix CVE-2020-9771

No vendor patch reference has been recorded for CVE-2020-9771 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2020-9771

1 tracked threat in the Threadlinqs corpus references CVE-2020-9771, either in the campaign’s CVE list or as an indicator on the campaign record.

- [AmnesiaStealer: macOS Infostealer Hijacks Live Browser Sessions via Chrome DevTools Protocol Remote Control](https://intel.threadlinqs.com/threat/TL-2026-2029) — HIGH · 2026-08-16

## Sources

Enriched from CVE.org, FIRST EPSS, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-10-10.

**Other references**

- [support.apple.com](https://support.apple.com/kb/HT211100)

Canonical: https://intel.threadlinqs.com/cve/CVE-2020-9771
Full detection coverage and IOCs for threats exploiting CVE-2020-9771 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp