CVE-2021-30666 (GCVE-0-2021-30666)

Vulnerability from cvelistv5 – Published: 2021-09-08 14:25 – Updated: 2025-10-21 23:25
VLAI? CISA
Summary
A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 12.5.3. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..
Severity ?
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.
Assigner
References
Impacted products
Vendor Product Version
Apple iOS Affected: unspecified , < 12.5 (custom)
Create a notification for this product.
CISA Known Exploited Vulnerability
Data from the CISA Known Exploited Vulnerabilities Catalog

Date added: 2021-11-03

Due date: 2021-11-17

Required action: Apply updates per vendor instructions.

Used in ransomware: Unknown

Notes: https://nvd.nist.gov/vuln/detail/CVE-2021-30666

Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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