CASCACascade Atlas

Evidence dossier

CVE-2026-96655

Plex Media Server arbitrary-host SSRF

Exploited in the wild (CISA KEV since Oct 20, 2026). cisa-cg reports CVSS 4.0 5.3. EPSS estimates 0.5% exploit likelihood as of Oct 22, 2026.

54.6–58.8Priority evidence range
Evidence through Oct 22, 2026, 6:07 PM UTC

As of Oct 22, 2026

Normalized restatement

Plex Media Server before 1.43.3.10861 allows an authenticated user to request arbitrary internal or external addresses via the '/video/:/transcode/universal' path parameter.

State
PUBLISHED
Published
Sep 23, 2026
Updated
Oct 21, 2026
Evidence coverage
85%

Evidence chronology

What was known when

Download this view's receipt →
  1. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Plex Media Server Server-Side Request Forgery (SSRF) Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Plex Media Server Server-Side Request Forgery (SSRF) Vulnerability
    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
    cisa-cg

    Record text: Plex Media Server arbitrary-host SSRF

    Inspect raw assertion
    Field
    container
    Value
    Plex Media Server arbitrary-host SSRF
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 0.46% probability · 38.53th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.004550000000; percentile 0.385270000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Oct 20, 2026 · first observed Oct 21, 2026

Exploit likelihood0.46%

FIRST EPSS · score date Oct 22, 2026 · 38.5th percentile · first observed Oct 22, 2026

SeverityCVSS 5.3

cisa-cg · CVSS 4.0 · first observed Oct 21, 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 statusLast verified source snapshot retained

The last verified source boundary remains in force for this claim.

Revision
evidence-policy-v1.1.0
Cutoff
Oct 22, 2026
Resolution
Review source contract
Exploit likelihoodEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Oct 22, 2026
Resolution
None
Severity assessmentEvidence supported

Eligible evidence is present for this bounded claim.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Oct 22, 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
Oct 22, 2026
Resolution
Resolve identity

Source comparison

Who said what

CISA KEVOriginal assertion
Exploitation cataloged

Plex Media Server Server-Side Request Forgery (SSRF) Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Plex Media Server Server-Side Request Forgery (SSRF) Vulnerability
Source dateFirst 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 ↗
cisa-cgOriginal assertion
Record text

Plex Media Server arbitrary-host SSRF

Inspect raw assertion
Field
container
Value
Plex Media Server arbitrary-host SSRF
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

0.46% probability · 38.53th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.004550000000; percentile 0.385270000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →

2 scope groups

cisa-cg · source assertedPlexMedia ServerDirect source scope
Affected: 0 to before 1.43.3.10861 (custom comparison)Unaffected: 1.43.3.10861
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "0", "lessThan": "1.43.3.10861", "versionType": "custom"}, {"status": "unaffected", "version": "1.43.3.10861"}]
NVD · source assertedVendor unspecified by sourceProduct unspecified by sourceDirect source scope
Version bounds not stated
Scope supported
Inspect raw assertioncpe:2.3:a:plex:media_server:*:*:*:*:*:*:*:*; end excluding 1.43.3.10861

Affected-product evidence

Accepted scope and product mapping

0 canonical links · 2 source-reported links

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
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Oct 22, 2026
Retained assertion IDs
a0f3779d-a5f2-41a0-9141-a3ab7d99249c
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
Nvd cpe vulnerable target
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Oct 22, 2026
Retained assertion IDs
94a73bd6-b77e-48de-a8fb-7cdc24008c3b

Assessments

CVSS by origin

5.3
CVE Program sourceCVSS 4.0 · role Secondary · priority eligiblevalid_matchCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
4.3
CVE Program sourceCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
5.3
cisa-cgCVSS 4.0 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
4.3
cisa-cgCVSS 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:N/A:N

Direct CVE/CNA normalized decisions

5.3Priority eligible

cisa-cg

CVSS 4.0 · Primary · Original assertion · rank 1

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Validation
Valid match
Recomputed
5.3
Decision reason
Evidence supported
Policy
casca-direct-cvss-eligibility-v1
4.3Priority eligible

cisa-cg

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Validation
Valid match
Recomputed
4.3
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.