CVE-2026-111633

Status: DeferredHigh (8.8)—
Severity8.8High · CVSS 4.0
Exploitation probability0.34 %higher than 26% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

ZKEACMS through 4.4 contains an authentication bypass vulnerability that allows unauthenticated attackers to forge REST API JWT bearer tokens using a hard-coded HMAC-SHA256 signing key in JwtBearerDefaults.cs. Attackers can sign a token with the Name claim set to 'admin' to call ApiAuthorize endpoints, modifying articles and products and reading form submissions.

CVSS

Base score
8.8
Version
4.0
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/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
0.34 %
Percentile among all scored CVEs
26
Score date
10/21/2026

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.

Vector AV:N/PR:N/UI:N y el texto indica que atacantes sin autenticar falsifican JWT con clave HMAC codificada, lo que permite modificar artículos/productos y leer envíos de formularios.

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

Affected technologies (1)

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

CWEs

References

Show 5 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-111633",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "disclosure@vulncheck.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 8.6,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "LOW",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "LOW"
        },
        "impactScore": 4.7,
        "exploitabilityScore": 3.9
      }
    ],
    "cvssMetricV40": [
      {
        "type": "Secondary",
        "source": "disclosure@vulncheck.com",
        "cvssData": {
          "Safety": "NOT_DEFINED",
          "version": "4.0",
          "Recovery": "NOT_DEFINED",
          "baseScore": 8.8,
          "Automatable": "NOT_DEFINED",
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/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",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "subIntegrityImpact": "NONE",
          "vulnIntegrityImpact": "HIGH",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "vulnAvailabilityImpact": "LOW",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "NONE",
          "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"
        }
      }
    ]
  },
  "affected": [
    {
      "source": "disclosure@vulncheck.com",
      "affectedData": [
        {
          "repo": "https://github.com/SeriaWei/ZKEACMS",
          "vendor": "SeriaWei",
          "product": "ZKEACMS",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "versionType": "custom",
              "lessThanOrEqual": "4.4"
            }
          ],
          "packageURL": "pkg:github/SeriaWei/ZKEACMS",
          "defaultStatus": "unaffected"
        }
      ]
    }
  ],
  "published": "2026-10-16T18:17:43.607",
  "references": [
    {
      "url": "https://github.com/SeriaWei/ZKEACMS/blob/v4.4/src/ZKEACMS/Api/JwtBearerDefaults.cs#L14-L19",
      "source": "disclosure@vulncheck.com"
    },
    {
      "url": "https://github.com/SeriaWei/ZKEACMS/blob/v4.4/src/ZKEACMS/BuilderAuthentication.cs#L41-L52",
      "source": "disclosure@vulncheck.com"
    },
    {
      "url": "https://github.com/SeriaWei/ZKEACMS/issues/531",
      "source": "disclosure@vulncheck.com"
    },
    {
      "url": "https://hackmd.io/@hieuPenguinnn/zkeacms-hardcoded-jwt-signing-key-admin-auth-bypass",
      "source": "disclosure@vulncheck.com"
    },
    {
      "url": "https://www.vulncheck.com/advisories/zkeacms-through-4.4-authentication-bypass-via-hard-coded-jwt-signing-key",
      "source": "disclosure@vulncheck.com"
    }
  ],
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "disclosure@vulncheck.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-321"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "ZKEACMS through 4.4 contains an authentication bypass vulnerability that allows unauthenticated attackers to forge REST API JWT bearer tokens using a hard-coded HMAC-SHA256 signing key in JwtBearerDefaults.cs. Attackers can sign a token with the Name claim set to 'admin' to call ApiAuthorize endpoints, modifying articles and products and reading form submissions."
    }
  ],
  "lastModified": "2026-10-16T19:04:35.840",
  "sourceIdentifier": "disclosure@vulncheck.com"
}