CASCACascade Atlas

Evidence dossier

CVE-2023-35311

Microsoft Outlook Security Feature Bypass Vulnerability

Exploited in the wild (CISA KEV since Jul 11, 2023). microsoft reports CVSS 3.1 8.8. Severity assessments differ within at least one CVSS version. EPSS estimates 15.5% exploit likelihood as of Aug 27, 2026.

71.3–78.5Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

Microsoft Outlook Security Feature Bypass Vulnerability

State
PUBLISHED
Published
Jul 11, 2023
Updated
Oct 21, 2025
Evidence coverage
80%

Evidence chronology

What was known when

Download this view's receipt →
  1. 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 ↗
  2. 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 ↗
  3. Source dateSource date omittedFirst observed by CASCA
    microsoft

    Record text: Microsoft Outlook Security Feature Bypass Vulnerability

    Inspect raw assertion
    Field
    container
    Value
    Microsoft Outlook Security Feature Bypass Vulnerability
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Microsoft Outlook Security Feature Bypass Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Microsoft Outlook Security Feature Bypass Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 15.52% probability · 96.55th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.155220000000; percentile 0.965510000000
    Original evidence ↗

Assessments differ

CVE Program source7.5CVSS 3.1 · source date omitted
NVD7.5CVSS 3.1 · source date omitted
secure@microsoft.com8.8CVSS 3.1 · source date omitted

Values are shown separately by source and CVSS version.

ExploitationCatalog member

CISA KEV · catalog date Jul 11, 2023 · first observed Jul 19, 2026

Exploit likelihood15.52%

FIRST EPSS · score date Aug 27, 2026 · 96.6th percentile · first observed Aug 27, 2026

SeverityAssessments differ

microsoft · CVSS 3.1 · first observed Jul 19, 2026 · values shown separately below

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 assessmentAssessments differ

Eligible assertions materially conflict and remain visible side by side.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Aug 27, 2026
Resolution
Resolve conflict
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

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 ↗
microsoftOriginal assertion
Record text

Microsoft Outlook Security Feature Bypass Vulnerability

Inspect raw assertion
Field
container
Value
Microsoft Outlook Security Feature Bypass Vulnerability
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Microsoft Outlook Security Feature Bypass Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Microsoft Outlook Security Feature Bypass Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

15.52% probability · 96.55th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.155220000000; percentile 0.965510000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
6Underlying assertions
4Canonical products
6Target 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

10 scope groups

microsoft · source assertedMicrosoftMicrosoft 365 Apps for EnterpriseDirect source scope
Affected: 16.0.1 to before https://aka.ms/OfficeSecurityReleases (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "16.0.1", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom"}]
microsoft · source assertedMicrosoftMicrosoft Office 2019Direct source scope
Affected: 19.0.0 to before https://aka.ms/OfficeSecurityReleases (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "19.0.0", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom"}]
microsoft · source assertedMicrosoftMicrosoft Office LTSC 2021Direct source scope
Affected: 16.0.1 to before https://aka.ms/OfficeSecurityReleases (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "16.0.1", "lessThan": "https://aka.ms/OfficeSecurityReleases", "versionType": "custom"}]
microsoft · source assertedMicrosoftMicrosoft Outlook 2013Direct source scope
Affected: 14.0.0 to before 15.0.5571.1000 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "14.0.0", "lessThan": "15.0.5571.1000", "versionType": "custom"}]
microsoft · source assertedMicrosoftMicrosoft Outlook 2013 Service Pack 1Direct source scope
Affected: 15.0.0.0 to before 15.0.5571.1000 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "15.0.0.0", "lessThan": "15.0.5571.1000", "versionType": "custom"}]
microsoft · source assertedMicrosoftMicrosoft Outlook 2016Direct source scope
Affected: 16.0.0.0 to before 16.0.5404.1000 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "16.0.0.0", "lessThan": "16.0.5404.1000", "versionType": "custom"}]
NVD CPE · APPLICATIONmicrosoft365_appsVulnerable target · 1 assertions
Version not applicableCanonical identity product-14a59f3c1c4fc4cec4da9e1d602ac339da114e67c884352e121c41fb03b7a712Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    40c15edd-98d4-4d06-ba06-21ae0f33c72d
NVD CPE · APPLICATIONmicrosoftofficeVulnerable target · 1 assertions
Version 2019Canonical identity product-f4efee17050cd92d62299077c43827052b373ddcb783c02caa43c2fbb378d2f4Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    ff177984-a906-43fa-bf60-298133fbbd6b
NVD CPE · APPLICATIONmicrosoftoffice_long_term_servicing_channelVulnerable target · 1 assertions
Version 2021Canonical identity product-911e466d0be7cb2953297756c47cb44a2f472c517f89b133f4ff5b03a0ab5264Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    0b3ef1e5-4757-4cfa-ae72-6ba876d3c9fd
NVD CPE · APPLICATIONmicrosoftoutlookVulnerable target · 3 assertions
Version 2013; Version 2016Canonical identity product-b312c98eb5c91fc7c3e69712233ab82c14dbc3f5723b9932de5a535b454ad87cLinked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:a:microsoft:outlook:2013:-:-:*:-:-:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 3
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    77f369d5-6771-4141-a116-50fb275a937a
  2. cpe:2.3:a:microsoft:outlook:2013:sp1:*:*:rt:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 4
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    dda98a76-d0d1-4bfa-beac-1c2313f7b859
  3. cpe:2.3:a:microsoft:outlook:2016:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 5
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    e2b1657c-0ff4-461a-be2a-641275c4b0a0

Affected-product evidence

Accepted scope and product mapping

4 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-14a59f3c1c4fc4cec4da9e1d602ac339da114e67c884352e121c41fb03b7a712

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
886bf3c3-9b80-4f8e-b530-9a1c659842fd
Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-911e466d0be7cb2953297756c47cb44a2f472c517f89b133f4ff5b03a0ab5264

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
8f75cd46-658c-46e2-af3c-fa516c86e6c1
Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-b312c98eb5c91fc7c3e69712233ab82c14dbc3f5723b9932de5a535b454ad87c

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
0ff3700b-6bf6-4cd3-b9da-70873fb8dd185700d5b6-a54b-4560-b7d7-6b2c45455575a76068e5-a407-4a2c-9bcc-b3009eda83fa
Mapping establishedEvidence supported

vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-f4efee17050cd92d62299077c43827052b373ddcb783c02caa43c2fbb378d2f4

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
eb9708d3-cd7c-4683-83fb-c8eed271c8da
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
6
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
13bbc312-d9da-48ad-b70d-1227196efa194a4eaeed-cd40-4887-bf63-8689b06181fd5621cdad-6967-4e9c-a4b5-8ec04329b66760cc7e12-5c8a-42c9-82b5-c312d35faf7fab69ae49-7263-47fa-976e-97cf91710609db5620e0-dddc-4eed-8d7f-84093dcfbd99

Assessments

CVSS by origin

7.5
CVE Program sourceCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
7.5
NVDCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
8.8
secure@microsoft.comCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
7.5
CISA-ADPCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
8.8
microsoftCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

Direct CVE/CNA normalized decisions

8.8Priority eligible

microsoft

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Validation
Valid match
Recomputed
8.8
Decision reason
Evidence supported
Policy
casca-direct-cvss-eligibility-v1
7.5Priority eligible

CISA-ADP

CVSS 3.1 · Secondary · Independent enrichment · rank 2

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Validation
Valid match
Recomputed
7.5
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.