CVE-2021-30762Known exploitationNetwork attack vector

Code execution via WebKit use-after-free

Published Sep 8, 2021 · Updated Oct 21, 2025

Use-after-free in WebKit in Apple iOS before 12.5.4 allows remote attackers to execute arbitrary code via malicious web content. WebKit references freed memory while processing attacker-controlled page data; Apple has not disclosed the affected function or object. A user must cause WebKit to process the crafted content; successful exploitation runs code in the affected WebKit context, and CISA records active exploitation.

CVSS severity8.8
High
EPSS probability10.99%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in WebKit in Apple iOS before 12.5.4 allows remote attackers to execute arbitrary code via malicious web content. WebKit references freed memory while processing attacker-controlled page data; Apple has not disclosed the affected function or object. A user must cause WebKit to process the crafted content; successful exploitation runs code in the affected WebKit context, and CISA records active exploitation.

The record

CVE
CVE-2021-30762
Published
Sep 8, 2021
Updated
Oct 21, 2025
Vendor
Apple
Product
iOS
Classifications
CWE-416, T1658
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record 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 <12.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · iOSversion=unspecified <12.5

Published CVSS scores

8.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1658Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Reported exploitation

Technologies

Your stack

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Your stack

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