CVE-2021-30955

highpriority · track · 40EPSS 0.048 · 92 %ileexploit · PoCDEEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

7 exploits · PoC

Likely / severe?

4.79% (92nd) EPSS

CVSS 7.6 · high

Is it mine?

20 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

A race condition was addressed with improved state handling. This issue is fixed in macOS Monterey 12.1, watchOS 8.3, iOS 15.2 and iPadOS 15.2, tvOS 15.2. A malicious application may be able to execute arbitrary code with kernel privileges.

cvss

Technical severity, 0–10. One row per scoring source.

7.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–7.6

v2.07.6highAV:N/AC:H/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 4.9 · impact 10

v3.17highCVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1 · impact 5.9

v3.16.6mediumCVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-362USprimary

exploits (7)

Public proof-of-concept and weaponised exploit code.

GeoSn0w/Pentagram-exploit-testerA test app to check if your device is vulnerable to CVE-2021-30955PoC · poc_in_github
b1n4r1b01/desc_raceiOS 15.1 kernel exploit POC for CVE-2021-30955PoC · poc_in_github
markie-dev/desc_race_A15CVE-2021-30955 iOS 15.1.1 POC for 6GB RAM devices (A14-A15)PoC · poc_in_github
nickorlow/CVE-2021-30955-POCJake Jame's proof of concept wrapped into an iOS app for CVE-2021-30955PoC · poc_in_github
st-rnd/desc_race-1desc_race exploit for iOS 15.0 - 15.1.1 (with stable kernel r/w primitives) (CVE-2021-30955) PoC · poc_in_github
timb-machine-mirrors/jakeajames-CVE-2021-30955Clone from gistPoC · poc_in_github

affected products (20)

Products and version ranges known to be affected.

Apple iOS <15.2all versionscert_bundDE
Apple iPadall versionscert_bundDEcpe:/h:apple:ipad:-
Apple iPadOS <15.2all versionscert_bundDE
Apple iPhoneall versionscert_bundDEcpe:/h:apple:iphone:-
Apple macOS Big Sur <11.6.2all versionscert_bundDE
Apple macOS Catalinaall versionscert_bundDEcpe:/o:apple:mac_os:catalina
Apple macOS Monterey <12.1all versionscert_bundDE
Apple IOS< 15.2cert_bundDE
Apple iPadOS< 15.2cert_bundDE
Apple macOS≤ Monterey <12.1cert_bundDE
Apple macOS≤ Big Sur <11.6.2cert_bundDE
Apple iOS and iPadOSunspecified → 15.2enisa_euvdEU
Apple macOSunspecified → 12.1enisa_euvdEU
Apple macOSunspecified → 15.2enisa_euvdEU
Apple watchOSunspecified → 8.3enisa_euvdEU
apple ipados< 15.2nvdUScpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone os< 15.2nvdUScpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple macos< 12.1nvdUScpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
apple tvos< 15.2nvdUScpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
apple watchos< 8.3nvdUScpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-0489Apple iOS: Mehrere SchwachstellenDeutsch2021-12-13csaf · cert_bundDE
Ein entfernter, anonymer, physischer oder lokaler Angreifer kann mehrere Schwachstellen in Apple iOS, Apple iPadOS, Apple iPhone und Apple iPad ausnutzen, um beliebigen Programmcode auszuführen, beliebigen Programmcode mit Kernel-Privilegien auszuführen, seine Privilegien zu erweitern, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand zu verursachen, Sicherheitsmaßnahmen zu umgehen und Dateien zu manipulieren.
WID-SEC-W-2026-0631Apple macOS: Mehrere SchwachstellenDeutsch2021-12-13csaf · cert_bundDE
Ein entfernter, anonymer oder lokaler Angreifer kann mehrere Schwachstellen in Apple macOS ausnutzen, um beliebigen Programmcode auszuführen, beliebigen Programmcode mit Kernel-Privilegien auszuführen, seine Privilegien zu erweitern, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand zu verursachen und Sicherheitsmaßnahmen zu umgehen.

also known as (2)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2021-08-24modified 2026-06-17

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Related entries.

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+4134 more

references (17)

External citations — patches, advisories, analysis.

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