CVE-2026-111633
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.
- Exploitation
T1190Exploit Public-Facing Applicationinitial access95 % - Primary impact
T1550.001Application Access Tokenlateral movement80 % - Secondary impact
T1005Data from Local Systemcollection55 % - Secondary impact
T1565Data Manipulationimpact70 %
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
- CWE-321
References
Show 5 references
- https://github.com/SeriaWei/ZKEACMS/blob/v4.4/src/ZKEACMS/Api/JwtBearerDefaults.cs#L14-L19
- https://github.com/SeriaWei/ZKEACMS/blob/v4.4/src/ZKEACMS/BuilderAuthentication.cs#L41-L52
- https://github.com/SeriaWei/ZKEACMS/issues/531
- https://hackmd.io/@hieuPenguinnn/zkeacms-hardcoded-jwt-signing-key-admin-auth-bypass
- https://www.vulncheck.com/advisories/zkeacms-through-4.4-authentication-bypass-via-hard-coded-jwt-signing-key
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"
}