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CVE-2026-108725

Status: DeferredMedium (5.1)—
Severity5.1Medium · CVSS 4.0
Exploitation probability0.21 %higher than 11% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

Cheshire Cat AI core through 2.0.23 contains a stored cross-site scripting vulnerability in the uploads plugin that allows authenticated users to upload HTML files via POST /uploads without type restrictions. Attackers can send the public GET /uploads/{path} URL to a signed-in victim, executing script in the application origin with the victim's access_token cookie, including administrators.

CVSS

Base score
5.1
Version
4.0
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/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

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.21 %
Percentile among all scored CVEs
11
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.

XSS almacenado en plugin de uploads: atacante sube HTML malicioso (requiere autenticación) y víctima lo ejecuta al acceder a GET /uploads/{path}, exfiltrando cookies de sesión (access_token) con privilegios de administrador.

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

User TrainingRestrict Web-Based ContentApplication Developer GuidanceActive Directory ConfigurationUser Account ManagementPrivileged Account Management

Affected technologies (1)

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

Cheshire CAT AI — Cheshire CAT AIAI

CWEs

References

Show 5 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-108725",
  "cveTags": [],
  "metrics": {
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          "options": [
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          "version": "2.0.3",
          "timestamp": "2026-10-13T13:18:05.919586Z"
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          "Automatable": "NOT_DEFINED",
          "attackVector": "NETWORK",
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          "valueDensity": "NOT_DEFINED",
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          "modifiedAttackVector": "NOT_DEFINED",
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          "vulnAvailabilityImpact": "NONE",
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          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
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          "vulnConfidentialityImpact": "LOW",
          "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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          "vendor": "cheshire-cat-ai",
          "product": "core",
          "versions": [
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  "published": "2026-10-11T13:17:16.137",
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      "url": "https://github.com/cheshire-cat-ai/core/blob/c22731e7009ac89835b1d7b1cabc5989d998ec3e/src/cat/scaffold/plugins/uploads/endpoints.py#L28-L96",
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      "description": [
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          "value": "CWE-79"
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      ]
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    {
      "lang": "en",
      "value": "Cheshire Cat AI core through 2.0.23 contains a stored cross-site scripting vulnerability in the uploads plugin that allows authenticated users to upload HTML files via POST /uploads without type restrictions. Attackers can send the public GET /uploads/{path} URL to a signed-in victim, executing script in the application origin with the victim's access_token cookie, including administrators."
    }
  ],
  "lastModified": "2026-10-16T19:18:44.867",
  "sourceIdentifier": "disclosure@vulncheck.com"
}