CVE-2020-3906

Unsigned code execution via TCC logic flaw

Published Apr 1, 2020 · Updated Aug 4, 2024

A TCC logic flaw in Apple macOS Mojave 10.14.6 and Catalina 10.15.3 allows local users to bypass code-signing enforcement. Apple has not published the faulty TCC check or restriction that mishandles the crafted application. Exploitation requires a local user to cause the crafted application to run, allowing code that should fail signature enforcement to execute.

CVSS severity7.8
High
EPSS probability0.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A TCC logic flaw in Apple macOS Mojave 10.14.6 and Catalina 10.15.3 allows local users to bypass code-signing enforcement. Apple has not published the faulty TCC check or restriction that mishandles the crafted application. Exploitation requires a local user to cause the crafted application to run, allowing code that should fail signature enforcement to execute.

The record

CVE
CVE-2020-3906
Published
Apr 1, 2020
Updated
Aug 4, 2024
Vendor
Apple
Product
macOS
Classifications
T1553.001
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 1, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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 <macOS Catalina 10.15.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Apple · macOSversion=unspecified <macOS Catalina 10.15.4

Published CVSS scores

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

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

T1553.001Gatekeeper Bypass

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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