CVE-2021-30900

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.052 · 92 %ileDEEUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV

Likely / severe?

5.20% (92nd) EPSS

CVSS 9.3 · high

Is it mine?

7 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · cert_bund

added 2023-03-30remediate by 2023-04-20

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-26

Apple iOS, iPadOS, and macOS Out-of-Bounds Write Vulnerability

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 14.8.1 and iPadOS 14.8.1, iOS 15.1 and iPadOS 15.1. A malicious application may be able to execute arbitrary code with kernel privileges.

cvss

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

9.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.09.3highAV:N/AC:M/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 8.6 · impact 10

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.9

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondaryexploitability 1.8 · impact 5.9

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimary

affected products (7)

Products and version ranges known to be affected.

Apple iOS and iPadOSunspecified → 14.8enisa_euvdEU
Apple iOS and iPadOSunspecified → 15.1enisa_euvdEU
apple ipados< 14.8.1nvdUScpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple ipados= 15.0nvdUScpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone os< 14.8.1nvdUScpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple iphone os= 15.0nvdUScpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple macos< 11.6.1nvdUScpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-0804Apple iOS und iPadOS: Mehrere SchwachstellenDeutsch2021-10-26csaf · cert_bundDE
Ein entfernter, anonymer oder lokaler Angreifer kann mehrere Schwachstellen in Apple iPadOS und Apple iOS ausnutzen, um beliebigen Programmcode auszuführen, seine Rechte zu erweitern, Informationen offenzulegen, einen Denial of Service Zustand herbeizuführen, Sicherheitsvorkehrungen zu umgehen oder sonstige Auswirkungen zu verursachen.

also known as (2)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd cert_bund NVD CVE.org MITRE

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

related (16,096)

Related entries.

ID	severity	EPSS	exploitable	published
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An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 18.7.11 and iPadOS 18.7.11, iOS 26.7.1 and iPadOS 26.7.1, macOS Sequoia 15.8.1,…
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Out of bounds write in V8 in Google Chrome prior to 153.0.8010.36 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security…
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In the Linux kernel, the following vulnerability has been resolved: ipv6: account for fraggap on the paged allocation path In __ip6_append_data(), when the paged-allocation branc…
CVE-2026-53266US	—OT critical	0.93% (61st)	KEV	2026-06-25
In the Linux kernel, the following vulnerability has been resolved: netfilter: bridge: make ebt_snat ARP rewrite writable The ebtables SNAT target keeps the Ethernet source addre…
CVE-2026-11645US	—OT critical	2.44% (84th)	KEV	2026-06-09
Out of bounds read and write in V8 in Google Chrome prior to 149.0.7827.103 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium…

+16091 more

references (15)

External citations — patches, advisories, analysis.

scry

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