CVE-2021-30841

Arbitrary code execution via crafted dfont processing

Published Oct 19, 2021 · Updated Aug 3, 2024

Arbitrary code execution in Apple macOS FontParser before 11.6 allows attackers to run code by processing a maliciously crafted dfont file. Apple identifies FontParser as the locus and says improved checks resolved the issue, but has not disclosed the failed check or parser operation. User interaction is required to process the file, and successful exploitation runs arbitrary code in the affected processing context.

CVSS severity7.8
High
EPSS probability1.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Arbitrary code execution in Apple macOS FontParser before 11.6 allows attackers to run code by processing a maliciously crafted dfont file. Apple identifies FontParser as the locus and says improved checks resolved the issue, but has not disclosed the failed check or parser operation. User interaction is required to process the file, and successful exploitation runs arbitrary code in the affected processing context.

The record

CVE
CVE-2021-30841
Published
Oct 19, 2021
Updated
Aug 3, 2024
Vendor
Apple
Product
macOS
Classifications
T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 19, 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

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Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <11.6
  2. Affected versionversion=unspecified <14.8
  3. Affected versionversion=unspecified <15
  4. Affected versionversion=unspecified <2021
  5. Affected versionversion=unspecified <8

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Apple · macOSversion=unspecified <11.6; version=unspecified <14.8; version=unspecified <15; version=unspecified <2021; version=unspecified <8

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1204.002User Execution: Malicious File

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

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Your stack

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