Threats / Apple / CVE-2021-30761
CVE-2021-30761
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Apple iOS vulnerability
Apple iOS WebKit memory corruption vulnerability enabling code execution via maliciously crafted web content. Affects Safari and other WebKit-dependent applications.
Verdict
Today item — known-exploited.
Out-of-bounds write in WebKit allows remote code execution when processing hostile web content. Exploitation requires user interaction with malicious HTML. Active exploitation observed in the wild.
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
2 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03).
Probability (EPSS)
EPSS 0.10591 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apple, iOS. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-787 Out-of-bounds Write — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
Craft malicious HTML with out-of-bounds memory write payload targeting WebKit parser
Business
User device compromised through web browsing without additional user action beyond visiting site
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
Trigger memory corruption during HTML processing to achieve arbitrary code execution
Business
Attacker gains execution context with privileges of Safari or affected application
3
Lateral reach — past segmentation narrative 3
Attacker
Execute post-exploitation payload to establish persistence or exfiltrate data
Business
Confidentiality and integrity of user data at risk; device may be used for further attacks
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05