CASCACascade Atlas

Evidence dossier

CVE-2020-3837

A memory corruption issue was addressed with improved memory handling.

Exploited in the wild (CISA KEV since Jun 27, 2022). NVD reports CVSS 3.1 7.8. EPSS estimates 16.1% exploit likelihood as of Aug 27, 2026.

72.5–75.5Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 13.3.1 and iPadOS 13.3.1, macOS Catalina 10.15.3, tvOS 13.3.1, watchOS 6.1.2. An application may be able to execute arbitrary code with kernel privileges.

State
PUBLISHED
Published
Feb 27, 2020
Updated
Oct 21, 2025
Evidence coverage
93%

Evidence chronology

What was known when

Download this view's receipt →
  1. Source dateSource date omittedFirst observed by CASCA
    apple

    Record text: A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 13.3.1 and iPadOS 13.3.1, macOS Catalina 10.15.3, tvOS 13.3.1, watchOS 6.1.2. An application may be able to execute arbitrary code with kernel privileges.

    Inspect raw assertion
    Field
    container
    Value
    A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 13.3.1 and iPadOS 13.3.1, macOS Catalina 10.15.3, tvOS 13.3.1, watchOS 6.1.2. An application may be able to execute arbitrary code with kernel privileges.
    Original evidence ↗
  2. Source dateSource date omittedFirst observed by CASCA
    CISA-ADP

    Record text: CISA ADP Vulnrichment

    Inspect raw assertion
    Field
    container
    Value
    CISA ADP Vulnrichment
    Original evidence ↗
  3. Source dateSource date omittedFirst observed by CASCA
    CVE Program

    Record text: CVE Program Container

    Inspect raw assertion
    Field
    container
    Value
    CVE Program Container
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Apple Multiple Products Memory Corruption Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Apple Multiple Products Memory Corruption Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 16.11% probability · 96.68th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.161110000000; percentile 0.966800000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Jun 27, 2022 · first observed Jul 19, 2026

Exploit likelihood16.11%

FIRST EPSS · score date Aug 27, 2026 · 96.7th percentile · first observed Aug 27, 2026

SeverityCVSS 7.8

NVD · CVSS 3.1 · first observed Jul 19, 2026 · same-version scores align in this snapshot

Evidence detail

Source limits and decisions

Why each evidence state has this value

casca-unknown-reasons-v1
Exploitation statusEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Exploit likelihoodEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Severity assessmentEvidence supported

Eligible evidence is present for this bounded claim.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Aug 27, 2026
Resolution
None
Affected productsSource-reported scope

The cited source assertion is retained while canonical product linkage remains open.

Revision
casca-factor-d-obligations-v1
Cutoff
Aug 27, 2026
Resolution
Resolve identity

Source comparison

Who said what

appleOriginal assertion
Record text

A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 13.3.1 and iPadOS 13.3.1, macOS Catalina 10.15.3, tvOS 13.3.1, watchOS 6.1.2. An application may be able to execute arbitrary code with kernel privileges.

Inspect raw assertion
Field
container
Value
A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 13.3.1 and iPadOS 13.3.1, macOS Catalina 10.15.3, tvOS 13.3.1, watchOS 6.1.2. An application may be able to execute arbitrary code with kernel privileges.
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA-ADPIndependent enrichment
Record text

CISA ADP Vulnrichment

Inspect raw assertion
Field
container
Value
CISA ADP Vulnrichment
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CVE ProgramDerivative copy
Record text

CVE Program Container

Inspect raw assertion
Field
container
Value
CVE Program Container
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Apple Multiple Products Memory Corruption Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Apple Multiple Products Memory Corruption Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

16.11% probability · 96.68th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.161110000000; percentile 0.966800000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
5Underlying assertions
5Canonical products
5Target assertions
0Constraint assertions

Grouped from 1 configuration nodes in this exact snapshot. Visual grouping is navigational; asset exposure and root cause require cited evidence.

Identity source boundaries
  • Cpe dictionary1,775,266 records · observed through 2026-07-21T06:45:29.809Z27d65b0f-b718-4b4f-bb79-c47c68d09dfa
  • Cpe match643,502 records · observed through 2026-07-21T08:13:17.697Z955dae73-7302-438b-aee1-058d7cc5d48e

9 scope groups

apple · source assertedAppleiOSDirect source scope
Affected: unspecified to before iOS 13.3.1 and iPadOS 13.3.1 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "iOS 13.3.1 and iPadOS 13.3.1", "versionType": "custom"}]
apple · source assertedApplemacOSDirect source scope
Affected: unspecified to before macOS Catalina 10.15.3 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "macOS Catalina 10.15.3", "versionType": "custom"}]
apple · source assertedAppletvOSDirect source scope
Affected: unspecified to before tvOS 13.3.1 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "tvOS 13.3.1", "versionType": "custom"}]
apple · source assertedApplewatchOSDirect source scope
Affected: unspecified to before watchOS 6.1.2 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "watchOS 6.1.2", "versionType": "custom"}]
NVD CPE · OPERATING SYSTEMappleipadosVulnerable target · 1 assertions
Any version (unconstrained) (< 13.3.1)Canonical identity product-8e7094ac066248cd4828b6ec8e3a96d010ed1c68f6083af46638775d737da0adLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    through excluding 13.3.1
    Match ID
    3dd89b34-ea75-4559-a112-13b489b2502a
NVD CPE · OPERATING SYSTEMappleiphone_osVulnerable target · 1 assertions
Any version (unconstrained) (< 13.3.1)Canonical identity product-665d7155d02581979844685e7fca6c2680af997f9200af455887b1c71c483272Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    through excluding 13.3.1
    Match ID
    b4bfeaab-906e-4f49-a6db-5717badd8089
NVD CPE · OPERATING SYSTEMapplemac_os_xVulnerable target · 1 assertions
Any version (unconstrained) (< 10.15.3)Canonical identity product-94613e1f5039e71a9805f20421d56ac6a61e2707d3f97a08fdf6823a65dc7b76Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    through excluding 10.15.3
    Match ID
    65c519d7-6c7c-4dde-9d83-ee31e749aaff
NVD CPE · OPERATING SYSTEMappletvosVulnerable target · 1 assertions
Any version (unconstrained) (< 13.3.1)Canonical identity product-e5ea88731ef28ba75a5b40a72b650d8199d1f49ce8c4cd688de7cdb41dc8b9fbLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 3
    Logic
    OR
    Version bounds
    through excluding 13.3.1
    Match ID
    7c2b3ac9-fafe-4819-9538-a072b446be78
NVD CPE · OPERATING SYSTEMapplewatchosVulnerable target · 1 assertions
Any version (unconstrained) (< 6.1.2)Canonical identity product-1b28e85eba5cb27cd93d563b4ea63a555b916484cee543c65fdbe57d529fc0d1Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 4
    Logic
    OR
    Version bounds
    through excluding 6.1.2
    Match ID
    53578351-17eb-4c7e-b736-78f0d01af5da

Affected-product evidence

Accepted scope and product mapping

5 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-d6ed6f1e35de2e16a8a10f2ae364dab009bb2afadd609071b20da24d60ce2829 · product-1b28e85eba5cb27cd93d563b4ea63a555b916484cee543c65fdbe57d529fc0d1

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
ae503096-72b0-481c-b9b9-842e4520369e
Mapping establishedEvidence supported

vendor-d6ed6f1e35de2e16a8a10f2ae364dab009bb2afadd609071b20da24d60ce2829 · product-665d7155d02581979844685e7fca6c2680af997f9200af455887b1c71c483272

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
3e2d8274-9a01-4d28-93db-15ed1f5fb636
Mapping establishedEvidence supported

vendor-d6ed6f1e35de2e16a8a10f2ae364dab009bb2afadd609071b20da24d60ce2829 · product-8e7094ac066248cd4828b6ec8e3a96d010ed1c68f6083af46638775d737da0ad

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
a2dc46e2-8e85-46f1-9273-71e57ff93c4b
Mapping establishedEvidence supported

vendor-d6ed6f1e35de2e16a8a10f2ae364dab009bb2afadd609071b20da24d60ce2829 · product-94613e1f5039e71a9805f20421d56ac6a61e2707d3f97a08fdf6823a65dc7b76

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
07190382-1562-4f74-a9ad-921846786826
Mapping establishedEvidence supported

vendor-d6ed6f1e35de2e16a8a10f2ae364dab009bb2afadd609071b20da24d60ce2829 · product-e5ea88731ef28ba75a5b40a72b650d8199d1f49ce8c4cd688de7cdb41dc8b9fb

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
bcb404e2-23c4-4777-9a3f-9fd460bf3fdd
Source-reported scopeSource-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Vendor specified only by source · Product specified only by source

Source class
Direct cve affected
Assertions
4
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
055b3dc9-563d-41d2-b5b2-b526f36262ea7ea08c65-64d5-4929-bedb-b82213acc44db41d83c0-e9bd-4494-b695-04dca5f05faffe7241fd-f394-46b4-9630-4b39395aacc5

Assessments

CVSS by origin

7.8
NVDCVSS 3.1 · role Primary · priority eligiblevalid_matchCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
9.3
NVDCVSS 2.0 · role Primary · priority eligiblevalid_matchAV:N/AC:M/Au:N/C:C/I:C/A:C
7.8
CVE Program sourceCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
7.8
CISA-ADPCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Direct CVE/CNA normalized decisions

7.8Priority eligible

CISA-ADP

CVSS 3.1 · Secondary · Independent enrichment · rank 2

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Validation
Valid match
Recomputed
7.8
Decision reason
Evidence supported
Policy
casca-direct-cvss-eligibility-v1

Assessments are retained side by side under closed precedence. Cascade never averages CVSS.

Evidence boundaries

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; remaining scope stays source-scoped.
  • NVD-carried upstream facts remain derivative; independent corroboration requires a separately authored source.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.
  • OSV aggregation and OSV-converted NVD material are not independent corroboration.
  • Red Hat facts are vendor assertions for the exact supplied products.
  • Nonmembership and not-yet-observed states are not proof of safety.