CASCACascade Atlas

Evidence dossier

CVE-2025-55177

Incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac…

Exploited in the wild (CISA KEV since Sep 2, 2025). facebook reports CVSS 3.1 5.4. EPSS estimates 4.2% exploit likelihood as of Aug 27, 2026.

61.1–64.1Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

Incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac v2.25.21.78 could have allowed an unrelated user to trigger processing of content from an arbitrary URL on a target’s device. We assess that this vulnerability, in combination with an OS-level vulnerability on Apple platforms (CVE-2025-43300), may have been exploited in a sophisticated attack against specific targeted users.

State
PUBLISHED
Published
Aug 29, 2025
Updated
Feb 26, 2026
Evidence coverage
92%

Evidence chronology

What was known when

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  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
    facebook

    Record text: Incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac v2.25.21.78 could have allowed an unrelated user to trigger processing of content from an arbitrary URL on a target’s device. We assess that this vulnerability, in combination with an OS-level vulnerability on Apple platforms (CVE-2025-43300), may have been exploited in a sophisticated attack against specific targeted users.

    Inspect raw assertion
    Field
    container
    Value
    Incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac v2.25.21.78 could have allowed an unrelated user to trigger processing of content from an arbitrary URL on a target’s device. We assess that this vulnerability, in combination with an OS-level vulnerability on Apple platforms (CVE-2025-43300), may have been exploited in a sophisticated attack against specific targeted users.
    Original evidence ↗
  3. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Meta Platforms WhatsApp Incorrect Authorization Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Meta Platforms WhatsApp Incorrect Authorization Vulnerability
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 4.21% probability · 90.23th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.042070000000; percentile 0.902300000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Sep 2, 2025 · first observed Jul 19, 2026

Exploit likelihood4.21%

FIRST EPSS · score date Aug 27, 2026 · 90.2th percentile · first observed Aug 27, 2026

SeverityCVSS 5.4

facebook · 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

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 ↗
facebookOriginal assertion
Record text

Incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac v2.25.21.78 could have allowed an unrelated user to trigger processing of content from an arbitrary URL on a target’s device. We assess that this vulnerability, in combination with an OS-level vulnerability on Apple platforms (CVE-2025-43300), may have been exploited in a sophisticated attack against specific targeted users.

Inspect raw assertion
Field
container
Value
Incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac v2.25.21.78 could have allowed an unrelated user to trigger processing of content from an arbitrary URL on a target’s device. We assess that this vulnerability, in combination with an OS-level vulnerability on Apple platforms (CVE-2025-43300), may have been exploited in a sophisticated attack against specific targeted users.
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Meta Platforms WhatsApp Incorrect Authorization Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Meta Platforms WhatsApp Incorrect Authorization Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

4.21% probability · 90.23th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.042070000000; percentile 0.902300000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
3Underlying assertions
2Canonical products
3Target 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

5 scope groups

facebook · source assertedFacebookWhatsApp Business for iOSDirect source scope
Affected: 2.22.25.2 to before 2.25.21.78 (semver comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "2.22.25.2", "lessThan": "2.25.21.78", "versionType": "semver"}]
facebook · source assertedFacebookWhatsApp Desktop for MacDirect source scope
Affected: 2.22.25.2 to before 2.25.21.78 (semver comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "2.22.25.2", "lessThan": "2.25.21.78", "versionType": "semver"}]
facebook · source assertedFacebookWhatsApp for iOSDirect source scope
Affected: 2.22.25.2 to before 2.25.21.73 (semver comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "2.22.25.2", "lessThan": "2.25.21.73", "versionType": "semver"}]
NVD CPE · APPLICATIONwhatsappwhatsappVulnerable target · 2 assertions
Any version (unconstrained) (>= 2.22.25.2, < 2.25.21.73); Any version (unconstrained) (>= 2.22.25.2, < 2.25.21.78)Canonical identity product-5acab13ac246a84584f0c6ae6ef577aab00ee96d12331a968788aa326716a91fLinked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:a:whatsapp:whatsapp:*:*:*:*:*:macos:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    from including 2.22.25.2; through excluding 2.25.21.78
    Match ID
    ca1a1b3a-90a5-4ea1-ac4b-715127ce9de7
  2. cpe:2.3:a:whatsapp:whatsapp:*:*:*:*:*:iphone_os:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 2.22.25.2; through excluding 2.25.21.73
    Match ID
    ad89de9c-ce23-499f-8436-3da8b2a2ecf4
NVD CPE · APPLICATIONwhatsappwhatsapp_businessVulnerable target · 1 assertions
Any version (unconstrained) (>= 2.22.25.2, < 2.25.21.78)Canonical identity product-566877caac9a8eedd487df6a7163b013608001dbed6aa9865eb8387cf6d96e1aLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:a:whatsapp:whatsapp_business:*:*:*:*:*:iphone_os:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    from including 2.22.25.2; through excluding 2.25.21.78
    Match ID
    5de9273b-2da9-4bce-8840-cb0b63163646

Affected-product evidence

Accepted scope and product mapping

2 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-b95afa17d98aee3ead08f2402bcd6a8c91d87b65192dc9217e286b9bf1453098 · product-566877caac9a8eedd487df6a7163b013608001dbed6aa9865eb8387cf6d96e1a

Source class
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
eb89e88d-720d-4f10-bd08-c8bff97e7f25
Mapping establishedEvidence supported

vendor-b95afa17d98aee3ead08f2402bcd6a8c91d87b65192dc9217e286b9bf1453098 · product-5acab13ac246a84584f0c6ae6ef577aab00ee96d12331a968788aa326716a91f

Source class
Nvd cpe vulnerable target
Assertions
2
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
1d1ff6b2-be48-4e17-8ce1-163c56e32b1688bb33be-ea9c-414b-9770-fa5da9fd3598
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
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
0065b697-6833-4062-80a5-c9571cf9368fae097fc1-acbf-4157-a55c-e08fc5bfae69cc65a0c9-0eb5-4163-89b0-49dfcba73795

Assessments

CVSS by origin

5.4
cve-assign@fb.comCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
5.4
facebookCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N/E:F/RL:O/RC:C

Direct CVE/CNA normalized decisions

5.4Priority eligible

facebook

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N/E:F/RL:O/RC:C
Validation
Valid match
Recomputed
5.4
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.