Skip to content

CVE-2021-30663

Integer Overflow: Is CVE-2021-30663 real, exploitable, or a false positive? Here's the community verdict.

signals

public sources

Exploited in wild
Yes
CISA KEV
Public exploit
None known
Metasploit/EDB/PoC
Base severity
8.8 High
CVSS
Exploitation prob.
4%
FIRST EPSS
Weakness
CWE-190 · Integer Overflow
CWE

Confirmed exploited in the wild. Patch this first, regardless of the base score.

baseline read

auto · not a community verdict

Real — exploited in the wild

CISA confirms active exploitation. Treat scanner hits as true positives unless your specific version or config is unaffected.

Based on CISA KEV

Confirm or dispute →

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

An integer overflow was addressed with improved input validation. This issue is fixed in iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, Safari 14.1.1, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution.

Published

Embed this verdict
TruePositive verdict for CVE-2021-30663
Markdown
[![TruePositive verdict](https://www.truepositive.app/cve/CVE-2021-30663/badge.svg)](https://www.truepositive.app/cve/CVE-2021-30663)
HTML
<a href="https://www.truepositive.app/cve/CVE-2021-30663"><img src="https://www.truepositive.app/cve/CVE-2021-30663/badge.svg" alt="TruePositive verdict for CVE-2021-30663"></a>

Live badge that updates automatically as the community verdict changes.

Community ground truth

Be the first practitioner to weigh in

So far this is only TruePositive's editorial baseline from public sources. Add your real-world verdict below — it becomes the signal the next person triaging this relies on.

🥇 The first 50 practitioners to contribute earn a Founding Contributor badge.

In your experience, is this finding real and exploitable?

awaiting field verdicts
Real, but not a risk here
Not a real issue

Curated baseline: TruePositive's read from public sources is Real & exploitable — a starting point, not a community verdict.

No account needed. Anonymous verdicts post as an unverified signal. Log in to make yours verified and earn reputation.

Field notes & remediation

Verdicts are the quick signal. Notes are the evidence and fixes behind them.

  • 0
    Field note · TruePositive EditorialCurated

    Apple Multiple Products WebKit Integer Overflow Vulnerability — Apple iOS, iPadOS, macOS, tvOS, and Safari WebKit contain an integer overflow vulnerability that leads to code execution when processing maliciously crafted web content. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing. Listed in the CISA KEV catalog (added 2021-11-03) — confirmed exploited in the wild, not theoretical. FIRST EPSS puts the chance of exploitation in the next 30 days at ~4%. Treat it as real and prioritize remediation over triage.

  • 0
    Remediation · TruePositive EditorialCurated

    Required action for Apple Multiple Products: Apply updates per vendor instructions. CISA set a federal remediation due date of 2021-11-17. After patching, verify the vulnerable path is no longer reachable before closing the finding.

Add a field note or remediationoptional
Note type

What are you adding?

Markdown supported · minimum 20 characters.

Same weakness: CWE-190 · Integer Overflow.