Exploitation evidence
Known exploited · CISA KEV listed
Added 2021-11-03. Ransomware campaign use: Unknown.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2022-05-03. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
Apple / iOS
Default status: Not specified
- affected: unspecified to < iOS 13.5 and iPadOS 13.5 (custom)
Apple / iOS-1
Default status: Not specified
- affected: unspecified to < iOS 12.4.7 (custom)
Apple / watchOS
Default status: Not specified
- affected: unspecified to < watchOS 6.2.5 (custom)
Apple / watchOS-1
Default status: Not specified
- affected: unspecified to < watchOS 5.3.7 (custom)
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.02232,
"percentile": 0.83023
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.02232,
"percentile": 0.82915
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.02232,
"percentile": 0.82897
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.02232,
"percentile": 0.82888
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.02232,
"percentile": 0.82875
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.02232,
"percentile": 0.82848
}06 Nov 2026, 00:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
"containers": {
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],
"title": "CISA ADP Vulnrichment"
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],
"cna": {
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{
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],
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],
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},
{
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},
{
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}05 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.02232,
"percentile": 0.82836
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.02232,
"percentile": 0.82821
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.02232,
"percentile": 0.82789
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.02232,
"percentile": 0.82768
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2020-9819",
"cwes": [
"CWE-787"
],
"dateAdded": "2021-11-03",
"dueDate": "2022-05-03",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2020-9819",
"product": "iOS, iPadOS, and watchOS",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "Apple iOS, iPadOS, and watchOS Mail contains a memory corruption vulnerability that may allow heap corruption when processing a maliciously crafted mail message.",
"vendorProject": "Apple",
"vulnerabilityName": "Apple iOS, iPadOS, and watchOS Memory Corruption Vulnerability"
}