CASCACascade Atlas

Evidence dossier

CVE-2025-34026

Versa Concerto Actuator Authentication Bypass Information Leak

Exploited in the wild (CISA KEV since Jan 22, 2026). VulnCheck reports CVSS 4.0 9.2. EPSS estimates 81.9% exploit likelihood as of Aug 26, 2026.

83.7–85.3Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

The Versa Concerto SD-WAN orchestration platform is vulnerable to an authentication bypass in the Traefik reverse proxy configuration, allowing at attacker to access administrative endpoints. The internal Actuator endpoint can be leveraged for access to heap dumps and trace logs.This issue is known to affect Concerto from 12.1.2 through 12.2.0. Additional versions may be vulnerable.

State
PUBLISHED
Published
May 21, 2025
Updated
Jan 23, 2026
Evidence coverage
96%

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
    VulnCheck

    Record text: Versa Concerto Actuator Authentication Bypass Information Leak

    Inspect raw assertion
    Field
    container
    Value
    Versa Concerto Actuator Authentication Bypass Information Leak
    Original evidence ↗
  3. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Versa Concerto Improper Authentication Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Versa Concerto Improper Authentication Vulnerability
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 81.94% probability · 99.62th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.819400000000; percentile 0.996240000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Jan 22, 2026 · first observed Jul 19, 2026

Exploit likelihood81.94%

FIRST EPSS · score date Aug 26, 2026 · 99.6th percentile · first observed Aug 26, 2026

SeverityCVSS 9.2

VulnCheck · CVSS 4.0 · 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 ↗
VulnCheckOriginal assertion
Record text

Versa Concerto Actuator Authentication Bypass Information Leak

Inspect raw assertion
Field
container
Value
Versa Concerto Actuator Authentication Bypass Information Leak
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Versa Concerto Improper Authentication Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Versa Concerto Improper Authentication Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

81.94% probability · 99.62th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.819400000000; percentile 0.996240000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
3Underlying assertions
1Canonical 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

2 scope groups

VulnCheck · source assertedVersaConcertoDirect source scope
Affected: 12.1.2 through 12.2.0 (semver comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "12.1.2", "versionType": "semver", "lessThanOrEqual": "12.2.0"}]
NVD CPE · APPLICATIONversa-networksconcertoVulnerable target · 3 assertions
Any version (unconstrained) (>= 11.4.0, < 12.1.2); Version 12.1.2; Version 12.2.0Canonical identity product-add0392455cbd03b1361f22a0218ffbf5d97e7b5b9809488df018178a05b717fLinked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:a:versa-networks:concerto:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 11.4.0; through excluding 12.1.2
    Match ID
    78511d68-db7c-4b51-a603-3a6315d8729d
  2. cpe:2.3:a:versa-networks:concerto:12.1.2:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    bc56e615-fc18-48ff-b52e-2251b45a6b43
  3. cpe:2.3:a:versa-networks:concerto:12.2.0:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    bd1ac8c4-c516-49e7-ae0b-d9b5f209d928

Affected-product evidence

Accepted scope and product mapping

1 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-243f50901544d59583fa2002ce2cceea52c1510a81ee5c27c4eec6161a2348c8 · product-add0392455cbd03b1361f22a0218ffbf5d97e7b5b9809488df018178a05b717f

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
1e357e2c-2acf-4fac-aa07-0f0473cd31e22e8e5d5a-0c40-4c3c-99fb-e2c4c5438feac15d0bc2-826d-417c-8b1c-fa6ff9903c25
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
Aug 27, 2026
Retained assertion IDs
c0923b4a-4ff3-472f-ba74-cfcd8e4a2250

Assessments

CVSS by origin

7.5
NVDCVSS 3.1 · role Primary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
9.2
disclosure@vulncheck.comCVSS 4.0 · role Secondary · priority eligiblevalid_matchCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:L/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
9.2
VulnCheckCVSS 4.0 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:L/SA:N

Direct CVE/CNA normalized decisions

9.2Priority eligible

VulnCheck

CVSS 4.0 · Primary · Original assertion · rank 1

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:L/SA:N
Validation
Valid match
Recomputed
9.2
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.