CVE-2021-30876

Process-memory disclosure via AppleScript bounds failure

Published Aug 24, 2021 · Updated Aug 3, 2024

Out-of-bounds read in AppleScript in Apple macOS allows attackers to disclose process memory or terminate an application via a crafted binary. The AppleScript binary-processing path reads beyond an intended buffer because crafted input is not subjected to adequate bounds checks. A user or application must process the crafted binary; successful exploitation is limited to process-memory disclosure or an application crash.

CVSS severity7.1
High
EPSS probability0.89%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in AppleScript in Apple macOS allows attackers to disclose process memory or terminate an application via a crafted binary. The AppleScript binary-processing path reads beyond an intended buffer because crafted input is not subjected to adequate bounds checks. A user or application must process the crafted binary; successful exploitation is limited to process-memory disclosure or an application crash.

The record

CVE
CVE-2021-30876
Published
Aug 24, 2021
Updated
Aug 3, 2024
Vendor
Apple
Product
macOS
Classifications
CWE-125
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 24, 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 <12.0
  3. Affected versionversion=unspecified <2021

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Apple · macOSversion=unspecified <11.6; version=unspecified <12.0; version=unspecified <2021

Published CVSS scores

7.1NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:N/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.

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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

CWE-125Out-of-bounds Read

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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