Threats / Apple / CVE-2020-9819
CVE-2020-9819
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Apple iOS, iPadOS, and watchOS vulnerability
Apple iOS, iPadOS, and watchOS Mail contains a memory corruption vulnerability enabling heap corruption through maliciously crafted mail messages.
Verdict
Today item — known-exploited.
Out-of-bounds write vulnerability in Mail application allows remote code execution via specially crafted email. Active exploitation observed in the wild. Affects all three Apple platforms.
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 0.02178 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apple, iOS, iPadOS, and watchOS. 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
I craft a malicious email message designed to trigger out-of-bounds memory writes in the Mail application's parsing logic.
Business
User receives email that exploits Mail vulnerability, potentially compromising device security and user data.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I send the malicious email to a target user, relying on automatic mail synchronization or user preview actions to trigger the vulnerability.
Business
Attack surface expands across iOS, iPadOS, and watchOS ecosystems, affecting millions of Apple device users.
3
Lateral reach — past segmentation narrative 3
Attacker
I achieve heap corruption and gain code execution within the Mail application's process context.
Business
Attacker gains ability to read user emails, contacts, and potentially escalate privileges on the device.
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