CASCACascade Atlas

Evidence dossier

CVE-2018-19943

If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code.

Exploited in the wild (CISA KEV since May 24, 2022). NVD reports CVSS 3.1 5.4. Severity assessments differ within at least one CVSS version. EPSS estimates 17.7% exploit likelihood as of Aug 27, 2026.

64.6–75.8Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed these issues in the following QTS versions. QTS 4.4.2.1270 build 20200410 and later QTS 4.4.1.1261 build 20200330 and later QTS 4.3.6.1263 build 20200330 and later QTS 4.3.4.1282 build 20200408 and later QTS 4.3.3.1252 build 20200409 and later QTS 4.2.6 build 20200421 and later

State
PUBLISHED
Published
Oct 28, 2020
Updated
Oct 21, 2025
Evidence coverage
83%

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
    qnap

    Record text: If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed these issues in the following QTS versions. QTS 4.4.2.1270 build 20200410 and later QTS 4.4.1.1261 build 20200330 and later QTS 4.3.6.1263 build 20200330 and later QTS 4.3.4.1282 build 20200408 and later QTS 4.3.3.1252 build 20200409 and later QTS 4.2.6 build 20200421 and later

    Inspect raw assertion
    Field
    container
    Value
    If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed these issues in the following QTS versions. QTS 4.4.2.1270 build 20200410 and later QTS 4.4.1.1261 build 20200330 and later QTS 4.3.6.1263 build 20200330 and later QTS 4.3.4.1282 build 20200408 and later QTS 4.3.3.1252 build 20200409 and later QTS 4.2.6 build 20200421 and later
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: QNAP NAS File Station Cross-Site Scripting Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    QNAP NAS File Station Cross-Site Scripting Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 17.71% probability · 96.93th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.177050000000; percentile 0.969290000000
    Original evidence ↗

Assessments differ

NVD5.4CVSS 3.1 · source date omitted
NVD3.5CVSS 2.0 · source date omitted
security@qnapsecurity.com.tw8.0CVSS 3.1 · source date omitted

Values are shown separately by source and CVSS version.

ExploitationCatalog member

CISA KEV · catalog date May 24, 2022 · first observed Jul 19, 2026

Exploit likelihood17.71%

FIRST EPSS · score date Aug 27, 2026 · 96.9th percentile · first observed Aug 27, 2026

SeverityAssessments differ

NVD · 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 ↗
qnapOriginal assertion
Record text

If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed these issues in the following QTS versions. QTS 4.4.2.1270 build 20200410 and later QTS 4.4.1.1261 build 20200330 and later QTS 4.3.6.1263 build 20200330 and later QTS 4.3.4.1282 build 20200408 and later QTS 4.3.3.1252 build 20200409 and later QTS 4.2.6 build 20200421 and later

Inspect raw assertion
Field
container
Value
If exploited, this cross-site scripting vulnerability could allow remote attackers to inject malicious code. QNAP has already fixed these issues in the following QTS versions. QTS 4.4.2.1270 build 20200410 and later QTS 4.4.1.1261 build 20200330 and later QTS 4.3.6.1263 build 20200330 and later QTS 4.3.4.1282 build 20200408 and later QTS 4.3.3.1252 build 20200409 and later QTS 4.2.6 build 20200421 and later
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

QNAP NAS File Station Cross-Site Scripting Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
QNAP NAS File Station Cross-Site Scripting Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

17.71% probability · 96.93th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.177050000000; percentile 0.969290000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
16Underlying assertions
1Canonical products
16Target 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

6 scope groups

qnap · source assertedQNAP Systems Inc.QTSDirect source scope
Affected: unspecified to before 4.4.2.1270 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "4.4.2.1270", "versionType": "custom"}]
qnap · source assertedQNAP Systems Inc.QTSDirect source scope
Affected: unspecified to before 4.4.1.1261 (custom comparison)Affected: unspecified to before 4.3.6.1263 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "4.4.1.1261", "versionType": "custom"}, {"status": "affected", "version": "unspecified", "lessThan": "4.3.6.1263", "versionType": "custom"}]
qnap · source assertedQNAP Systems Inc.QTSDirect source scope
Affected: unspecified to before 4.3.4.1282 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "4.3.4.1282", "versionType": "custom"}]
qnap · source assertedQNAP Systems Inc.QTSDirect source scope
Affected: unspecified to before 4.3.3.1252 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "4.3.3.1252", "versionType": "custom"}]
qnap · source assertedQNAP Systems Inc.QTSDirect source scope
Affected: unspecified to before 4.2.6 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "unspecified", "lessThan": "4.2.6", "versionType": "custom"}]
NVD CPE · OPERATING SYSTEMqnapqtsVulnerable target · 16 assertions
Any version (unconstrained) (< 4.2.6); Any version (unconstrained) (>= 4.3.1.0013, < 4.3.3.1252); Any version (unconstrained) (>= 4.3.4, < 4.3.4.1282); Any version (unconstrained) (>= 4.3.6, < 4.3.6.1263); Any version (unconstrained) (>= 4.4.0, < 4.4.1.1261); Any version (unconstrained) (>= 4.4.2, < 4.4.2.1270); Version 4.2.6Canonical identity product-81578b5d517b13c57b34c6184dee501c7b2e69f5d366148b8e0d95265e548fc9Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:qnap:qts:4.2.6:build_20191107:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 11
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    f6259c86-ffda-40e8-af0c-33cc8c108dc9
  2. cpe:2.3:o:qnap:qts:4.2.6:build_20190322:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 8
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    1388dbe0-f6bb-44ab-81ac-bfb4e70be820
  3. cpe:2.3:o:qnap:qts:4.2.6:build_20200421:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 13
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    1d1e5368-9587-4e0a-bb65-d88069ca8490
  4. cpe:2.3:o:qnap:qts:4.2.6:build_20170517:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 7
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    8f523e9f-d101-4c29-a624-74e1f3f8cb7d
  5. cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    from including 4.3.1.0013; through excluding 4.3.3.1252
    Match ID
    32758edb-15ae-4d3e-a26a-1e5af0f9b629
  6. cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 3
    Logic
    OR
    Version bounds
    from including 4.3.6; through excluding 4.3.6.1263
    Match ID
    5a7a639d-e2b5-4f2d-97cf-319e6fe9e991
  7. cpe:2.3:o:qnap:qts:4.2.6:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 6
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    2d3b1e3a-c9e9-4bb8-8bfc-ae1258722f85
  8. cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 4
    Logic
    OR
    Version bounds
    from including 4.4.0; through excluding 4.4.1.1261
    Match ID
    1b943695-5b8e-4bd1-9788-baccff9c6afc
  9. cpe:2.3:o:qnap:qts:4.2.6:build_20190921:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 10
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    a1f11848-6fed-4d58-a177-36d280c0347c
  10. cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    from including 4.3.4; through excluding 4.3.4.1282
    Match ID
    253a2c3e-04b9-4237-b78e-d7fad881b1ec
  11. cpe:2.3:o:qnap:qts:4.2.6:build_20200821:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 15
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    886a71d1-9615-47a5-b3c2-cbc6f02961a4
  12. cpe:2.3:o:qnap:qts:4.2.6:build_20190730:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 9
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    cf3c4461-c1b6-43a1-ba5e-d6658efd06ee
  13. cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    through excluding 4.2.6
    Match ID
    3777f6cc-9189-4bc0-b336-62ba1efb91a7
  14. cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 5
    Logic
    OR
    Version bounds
    from including 4.4.2; through excluding 4.4.2.1270
    Match ID
    776a3547-3d39-46e7-85dd-5d117f164338
  15. cpe:2.3:o:qnap:qts:4.2.6:build_20200611:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 14
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    b63ce419-871c-4866-8ab1-4bb6461e1d74
  16. cpe:2.3:o:qnap:qts:4.2.6:build_20200109:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 12
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    9e01e157-bdf1-4b00-ba9b-6887c0c7dff2

Affected-product evidence

Accepted scope and product mapping

1 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-37a503905b0a0167877af753ac60ba6a9fd40363b081ec9e83c43aeaec72163a · product-81578b5d517b13c57b34c6184dee501c7b2e69f5d366148b8e0d95265e548fc9

Source class
Nvd cpe vulnerable target
Assertions
16
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
0a27e343-63f5-4615-8d8b-78eea88a0e2324dd90c2-9b7e-4602-8689-d4a7b55bcf192d0e0214-4fb1-400f-a912-daaf4682f9643a5923b9-ebdb-47de-b173-c2a3b73f85df60e93929-ff01-4a43-b92c-e629e6fc11287cd86c85-3b08-4975-9c3c-ec42b5fcbb088125663c-01ff-425b-a8e3-f008883ce65c93684350-c477-4145-9abd-71635d15871e9f879dea-1e0a-42d6-81c5-bf8a14e63abda5baf6db-5bd1-4200-9d6a-4295346d4e1ea7c3a986-ec7e-4eac-a8c6-1e7e68cbf5abb7d44c46-2091-40b3-8aae-08b6a0250463db6a892b-a295-42d2-a915-c3f2b13e3583e17b5507-8d6f-4593-80f0-0bb4fa2d450de623fb8f-602e-4ef9-a0cd-bf4b2a42dd8cff24034f-f3a5-4c00-bb4b-fadda0a22255
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
5
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
1b0b5641-c738-4984-8472-233c44953c575dc6d416-2838-4eef-9424-e70ad3c7d4e6709c9019-c00e-490b-b61a-00989c2ed57793a424ae-314f-47e2-93a4-4a56ecd0baacab210509-db2d-4e98-a359-f89090079298

Assessments

CVSS by origin

5.4
NVDCVSS 3.1 · role Primary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
3.5
NVDCVSS 2.0 · role Primary · priority eligiblevalid_matchAV:N/AC:M/Au:S/C:N/I:P/A:N
8.0
security@qnapsecurity.com.twCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
8.0
qnapCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H

Direct CVE/CNA normalized decisions

8.0Priority eligible

qnap

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
Validation
Valid match
Recomputed
8.0
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.