CVE-2021-30952: Apple Multiple Products Integer Overflow or Wraparound Vulnerability

Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.

Generated by VEDAS. Scores as of 2026-11-01 19:19 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.

What it is

An integer overflow was addressed with improved input validation. This issue is fixed in tvOS 15.2, macOS Monterey 12.1, Safari 15.2, iOS 15.2 and iPadOS 15.2, watchOS 8.3. Processing maliciously crafted web content may lead to arbitrary code execution.

Description quoted from the CVE record (assigned by apple, published 2021-08-24).

Weakness: CWE-190 Integer Overflow or Wraparound

How it can be exploited

Exploitable over the network with low attack complexity needing no privileges and a user must take an action. Impact: confidentiality high, integrity high, availability high. CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CISA assessment (SSVC): CISA assesses exploitation as active. Automatable: no. Technical impact: total.

On CISA KEV since
2026-03-05
US federal deadline
2026-03-26
Ransomware use
Not known

Public exploit evidence (Exploit Observer)

Also known as: BDU:2022-00098, CNNVD-202108-2056, EUVD-2021-17869

VEDAS cluster: VEDAS:ANTQUEEN

Exploit Observer has no public exploit code that names this CVE or one of its aliases.

Research and write-ups (1)

Vulnerability databases and vendor advisories (9)

Catalogue entries, not exploit evidence.

96 more references returned by Exploit Observer did not name this CVE or an alias, so they are left out.

VEDAS data as of 2026-11-01T17:12 UTC; fetched 2026-11-02.

Live scores

EPSS
0.070
some chance of attack soon
VEDAS
0.973
strong exploit evidence
On CISA KEV
Yes, since 2026-03-05
Detection rule
None yet
EPSS (chance of attack)
10No cve-scores data 2026-02-22 to 2026-08-08no data0.1Added to CISA KEV 2026-03-05CVE-2021-30952 EPSS over time2025-042026-11-01
VEDAS (exploit evidence)
10No cve-scores data 2026-02-22 to 2026-08-08no data0.9Added to CISA KEV 2026-03-05CVE-2021-30952 VEDAS over time2025-042026-11-01

Thin horizontal line: the “likely” (EPSS 0.10) or “strong” (VEDAS 0.90) threshold. Shaded “no data” areas are periods when cve-scores did not publish. The vertical line is the day CISA added it to its exploited list.

Who is affected

ProductAffectedNot affected
Apple watchOSbefore 8.3Not stated
Apple iOS and iPadOSbefore 15.2Not stated
Apple macOSbefore 12.1Not stated
Apple macOSbefore 15.2Not stated
Apple macOSbefore 15.2Not stated

Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.

Exploit Observer also maps it to: apple ipados, apple iphone_os, apple macos, apple safari, apple tvos, apple watchos, apple_inc. ios, apple_inc. ipados, apple_inc. macos, apple_inc. watchos.

How to fix it

Fixed versions stated in the CVE record: 8.3, 15.2, 12.1.

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Vendor guidance:

How to detect it

There is no open VEDAS detection rule for this bug yet. It is listed on the detection gaps page if CISA has confirmed attacks.

References

Vendor advisories and patches

Exploits and technical analysis

Government sources

Other references

Other databases

Where this comes from

This advisory is generated automatically by VEDAS from: CVE.org record, CISA KEV, cve-scores (EPSS and VEDAS), Exploit Observer. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.