CVE-2021-1815Public exploit

Protected filesystem modification via directory path parsing

Published Sep 8, 2021 · Updated Aug 3, 2024

Path traversal in Apple Preferences before macOS 11.3, iOS, iPadOS, and tvOS 14.5, and watchOS 7.4 lets local users alter protected files. On macOS, the root cfprefsd daemon accepts an attacker-chosen preference domain and creates missing directories at that path with attacker-controlled ownership. Local code execution is required; writable periodic-script paths can convert the filesystem modification into root code execution on macOS.

CVSS severity5.5
Medium
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Path traversal in Apple Preferences before macOS 11.3, iOS, iPadOS, and tvOS 14.5, and watchOS 7.4 lets local users alter protected files. On macOS, the root cfprefsd daemon accepts an attacker-chosen preference domain and creates missing directories at that path with attacker-controlled ownership. Local code execution is required; writable periodic-script paths can convert the filesystem modification into root code execution on macOS.

The record

CVE
CVE-2021-1815
Published
Sep 8, 2021
Updated
Aug 3, 2024
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-22, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <14.5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <14.5
Apple · tvOSversion=unspecified <14.5
Apple · macOSversion=unspecified <11.3
Apple · watchOSversion=unspecified <7.4

Published CVSS scores

2.1NIST NVDAV:L/AC:L/Au:N/C:N/I:P/A:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1068Exploitation for Privilege Escalation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo