CVE-2021-30807

Exp

A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Big Sur 11.5.1, iOS 14.7.1 and iPadOS 14.7.1, watchOS 7.6.1. An application may be able to execute arbitrary code with kernel privileges. Apple is aware of a report that this issue may have been actively exploited.

Published: 2021-10-19 Last update: 2025-10-23 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-30807 is rated Critical Active Threat (88.2/100): CVSS High severity, with high exploitation likelihood (EPSS 21.03%, 96th percentile). CISA KEV confirms active exploitation (added 2021-11-03) affecting Apple / Multiple Products. a weakness (CWE-787) Unauthenticated remote administrative access may be possible. The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2021-30807

Name: Apple Multiple Products Memory Corruption Vulnerability · CISA KEV detail

Exploit added: 2021-11-03

Action due: 2021-11-17

Required action: Apply updates per vendor instructions.

Exploit prediction scoring system (EPSS) score for CVE-2021-30807

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-20 22.52% 21.03% -1.50%
2 2026-05-04 24.45% 22.52% -1.93%
3 2026-03-17 — 24.45% —

Full EPSS history (27 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-30807

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0
9.3 2.0 HIGH
AV:N/AC:M/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 8.6 10.0 [email protected]

Weakness enumeration for CVE-2021-30807

Affected software / configurations for CVE-2021-30807

Vendor Product Version Raw CPE
apple ipados < 14.7.1 cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone_os < 14.7.1 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple macos < 11.5.1 cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
apple watchos < 7.6.1 cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

References for CVE-2021-30807

URL Tags
https://support.apple.com/en-us/HT212622 Release Notes Vendor Advisory
https://support.apple.com/en-us/HT212623 Release Notes Vendor Advisory
https://support.apple.com/en-us/HT212713 Release Notes Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30807 Third Party Advisory US Government Resource
cvelogic Threat Intelligence