Apple
Apple Multiple Products Integer Overflow or Wraparound Vulnerability
At a glance
Actively exploited in the wild — prioritise confirming exposure.
High rather than Critical: exposure is scored at a default because we cannot see your systems or suppliers. If you run or depend on Apple Multiple Products, treat it as Critical.
Briefing
- Do not treat uncorroborated claims as confirmed breaches.
Questions to ask IT
- Do we run Apple Multiple Products, and which versions?
- Is any of it reachable from the internet?
- Have we checked whether it has already been used against us?
- If it is still not patched, what mitigation is in place, and what is holding the fix up?
Next steps
- Confirm exposure, mitigation status and any service interruption risk.
Vulnerability facts
Full CVE detail CVE-2021-30952- 7.8 · HighExploitable only with local access without any account, but only if a user takes an action, such as opening a file or link. High impact on confidentiality, integrity and availability.CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Listed: attacks using it have been seen (on the catalogue since )
- ~7% estimated chance of attack in 30 days
No technical write-up beyond these facts and the summary below yet.
Next steps
- Confirm whether affected products/versions are present and prioritise patching or mitigations
Summary
- Apple tvOS, macOS, Safari, iPadOS and watchOS contain an integer overflow or wraparound vulnerability due to the processing of maliciously crafted web content that may lead to arbitrary code execution.
- CVE-2021-30952 is listed in known-exploited catalogue (exploitation in the wild)
- Authoritative catalogues report active exploitation of this vulnerability.
Why this matters in the UK
- Known-exploited catalogue reports exploitation in the wild
Products and services involved
- Apple Multiple Products98% match confidence · CVE-2021-30952
Pulse
Last checked 4d ago · Recheck overdue since 5 Nov 2026, 21:38 UK time · 4 quiet checks collapsed
in the next 30 days first recorded at 7.0% (lower likelihood signal, not confirmed exploitation).
recorded — watch for changes; not confirmed exploitation.
2 quiet checks hidden.
Sources
Apple Multiple Products Integer Overflow or Wraparound Vulnerability
How we know
Statements extracted from sources. Higher confidence means stronger corroboration.
- ConfirmedHeadline90% confidence
Apple Multiple Products Integer Overflow or Wraparound Vulnerability
- ConfirmedSummary fact75% confidence
Apple tvOS, macOS, Safari, iPadOS and watchOS contain an integer overflow or wraparound vulnerability due to the processing of maliciously crafted web content that may lead to arbitrary code execution. Affects Apple Multiple Products. Known ransomware campaign use: Unknown. 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.
- ConfirmedCVE identifier95% confidence
Event involves CVE-2021-30952
- ConfirmedKnown-exploited catalogue98% confidence
CVE-2021-30952 is listed in known-exploited catalogue (exploitation in the wild)

