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CVE-2026-108860

Status: DeferredCritical (9.3)—
Severity9.3Critical · CVSS 4.0
Exploitation probability0.48 %higher than 40% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

BotSharp through 5.2.0 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to forge bearer tokens using the hard-coded Jwt:Key in WebStarter appsettings.json. Attackers can sign tokens with the committed HMAC secret and fixed botsharp issuer and audience to impersonate any known user, including administrators, on Authorize-protected API routes.

CVSS

Base score
9.3
Version
4.0
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/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

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.48 %
Percentile among all scored CVEs
40
Score date
10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vulnerabilidad de bypass de autenticación remota en API sin requerir credenciales válidas (AV:N/PR:N/UI:N). Atacante forja tokens JWT con clave hardcodeada para suplantar usuarios administradores y obtener acceso a rutas protegidas.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Vulnerability ScanningPrivileged Account ManagementPassword PoliciesNetwork SegmentationMulti-factor AuthenticationLimit Access to Resource Over Network

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Botsharp — BotsharpAI

CWEs

References

Show 5 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-108860",
  "cveTags": [],
  "metrics": {
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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          "id": "CVE-2026-108860",
          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-14T16:47:16.407934Z"
        }
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    "cvssMetricV31": [
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          "integrityImpact": "HIGH",
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    ],
    "cvssMetricV40": [
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        "cvssData": {
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          "Automatable": "NOT_DEFINED",
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/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",
          "exploitMaturity": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED",
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          "subIntegrityImpact": "NONE",
          "vulnIntegrityImpact": "HIGH",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
        }
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  },
  "affected": [
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      "source": "disclosure@vulncheck.com",
      "affectedData": [
        {
          "repo": "https://github.com/SciSharp/BotSharp",
          "vendor": "SciSharp",
          "product": "BotSharp",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "versionType": "custom",
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  "published": "2026-10-11T14:17:05.933",
  "references": [
    {
      "url": "https://github.com/SciSharp/BotSharp",
      "source": "disclosure@vulncheck.com"
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    {
      "url": "https://github.com/SciSharp/BotSharp/blob/a11ee0317cab5c619df1cb5d0c4fc39d1b6e30b4/src/Infrastructure/BotSharp.OpenAPI/BotSharpOpenApiExtensions.cs#L46-L57",
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      "source": "disclosure@vulncheck.com"
    }
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      "source": "disclosure@vulncheck.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-321"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "BotSharp through 5.2.0 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to forge bearer tokens using the hard-coded Jwt:Key in WebStarter appsettings.json. Attackers can sign tokens with the committed HMAC secret and fixed botsharp issuer and audience to impersonate any known user, including administrators, on Authorize-protected API routes."
    }
  ],
  "lastModified": "2026-10-16T19:18:44.867",
  "sourceIdentifier": "disclosure@vulncheck.com"
}