Skip to main content
Meet us at Black Hat USA 2026— Las Vegas, August 1–6Book a Meeting
Mallory
Back to vulnerabilities
Unrated

Stack Overflow in Apple WebRTC leading to Safari crash

IdentifiersCVE-2026-43718CWE-121

CVE-2026-43718 is a stack overflow vulnerability in Apple’s WebRTC-related web content processing path. Apple states that the issue was addressed with improved input validation and that processing maliciously crafted web content may lead to an unexpected Safari crash. The vulnerability affects Safari 26.5.2 prior versions and the corresponding web-content stack in iOS 26.5.2, iPadOS 26.5.2, and macOS Tahoe 26.5.2. Based on the available information, the flaw is triggered during handling of attacker-controlled web content and results in a stack overflow condition causing browser instability.

Share:
For your environment

Are you exposed to this one?

Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.

Start free trial
ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can cause Safari to crash while processing maliciously crafted web content, resulting in denial of service to the browser session. The provided content does not establish code execution, sandbox escape, or data disclosure for this CVE specifically.

Mitigation

If you can’t patch tonight, do this now.

Until patches are applied, reduce exposure to untrusted web content, especially attacker-controlled pages that may exercise WebRTC functionality. Where operationally feasible, limit or disable use of Safari for untrusted browsing and restrict access to suspicious websites. No vendor-specific workaround beyond updating is provided in the supplied content.

Remediation

Patch, then assume compromise.

Apply Apple’s fixes by updating to Safari 26.5.2, iOS 26.5.2, iPadOS 26.5.2, and macOS Tahoe 26.5.2 or later. Apple indicates the issue was remediated through improved input validation in the affected component.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

ACTIVITY FEED

Recent activity

7 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

7 SOURCESView more in app
handlers diary fullNews
Jun 30, 2026
June 2026 Apple Updates - SANS Internet Storm Center

A WebRTC vulnerability in Apple platforms where malicious web content may cause Safari to crash unexpectedly.

Read more
apple supportNews
Jun 29, 2026
About the security content of iOS 26.5.2 and iPadOS 26.5.2 - Apple Support

A stack overflow vulnerability in web content processing that could cause an unexpected Safari crash.

Read more
apple supportNews
Jun 29, 2026
About the security content of macOS Tahoe 26.5.2 - Apple Support

A macOS Tahoe web content processing vulnerability involving stack overflow that may cause an unexpected Safari crash.

Read more
apple supportNews
Jun 29, 2026
About the security content of Safari 26.5.2 - Apple Support

A stack overflow vulnerability in Apple web content processing that could cause an unexpected Safari crash.

Read more
What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Start free trial
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity3

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES
MITRE CVE
cve.org · CVE-2026-43718
NVD
nvd.nist.gov/vuln/detail/CVE-2026-43718
MITRE CWE · CWE-121
cwe.mitre.org