CVE-2026-90474 (GCVE-0-2026-90474)
Vulnerability from cvelistv5 – Published: 2026-09-12 11:06 – Updated: 2026-09-12 11:06
VLAI
EPSS
VEX
Title
MCPHub before 1.0.32 OAuth 2.0 Authentication Bypass
Summary
MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges.
Severity
CWE
- CWE-287 - Improper Authentication
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/samanhappy/mcphub/security/adv… | third-party-advisoryvendor-advisory |
| https://github.com/samanhappy/mcphub/commit/e9276… | patch |
| https://github.com/samanhappy/mcphub/blob/v1.0.31… | technical-description |
| https://github.com/samanhappy/mcphub/releases/tag… | release-notes |
| https://www.vulncheck.com/advisories/mcphub-befor… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| samanhappy | mcphub |
Affected:
0 , < 1.0.32
(semver)
|
guessed |
Date Public
2026-08-23 07:25
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"packageURL": "pkg:npm/%40samanhappy/mcphub",
"product": "mcphub",
"vendor": "samanhappy",
"versions": [
{
"lessThan": "1.0.32",
"status": "affected",
"version": "0",
"versionType": "semver"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "Wayde Shi (PayPal Cyber Security Team)"
}
],
"datePublic": "2026-08-23T07:25:08.000Z",
"descriptions": [
{
"lang": "en",
"value": "MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges."
}
],
"metrics": [
{
"cvssV4_0": {
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 7.6,
"baseSeverity": "HIGH",
"privilegesRequired": "NONE",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "PASSIVE",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH"
},
"format": "CVSS"
},
{
"cvssV3_1": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.8,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-287",
"description": "Improper Authentication",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-12T11:06:12.925Z",
"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"shortName": "VulnCheck"
},
"references": [
{
"name": "GitHub Security Advisory (GHSA-3m7m-37xf-xp9x)",
"tags": [
"third-party-advisory",
"vendor-advisory"
],
"url": "https://github.com/samanhappy/mcphub/security/advisories/GHSA-3m7m-37xf-xp9x"
},
{
"name": "fix(security): enforce OAuth client auth and S256-only PKCE policy",
"tags": [
"patch"
],
"url": "https://github.com/samanhappy/mcphub/commit/e927620cd1a80e8691213b01eb8cd6ffa1a66e9f"
},
{
"name": "getClient() verifies a registered secret only when one is supplied, at v1.0.31",
"tags": [
"technical-description"
],
"url": "https://github.com/samanhappy/mcphub/blob/v1.0.31/src/services/oauthServerService.ts#L26-L38"
},
{
"name": "mcphub v1.0.32 Release Notes",
"tags": [
"release-notes"
],
"url": "https://github.com/samanhappy/mcphub/releases/tag/v1.0.32"
},
{
"name": "VulnCheck Advisory: MCPHub before 1.0.32 OAuth 2.0 Authentication Bypass",
"tags": [
"third-party-advisory"
],
"url": "https://www.vulncheck.com/advisories/mcphub-before-1.0.32-oauth-2.0-authentication-bypass"
}
],
"title": "MCPHub before 1.0.32 OAuth 2.0 Authentication Bypass",
"x_generator": {
"engine": "vulncheck-endgame"
}
}
},
"cveMetadata": {
"assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"assignerShortName": "VulnCheck",
"cveId": "CVE-2026-90474",
"datePublished": "2026-09-12T11:06:12.925Z",
"dateReserved": "2026-09-12T02:03:32.649Z",
"dateUpdated": "2026-09-12T11:06:12.925Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-90474",
"date": "2026-09-14",
"epss": "0.003",
"percentile": "0.2254"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-90474\",\"sourceIdentifier\":\"disclosure@vulncheck.com\",\"published\":\"2026-09-12T11:16:34.483\",\"lastModified\":\"2026-09-12T11:16:34.483\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges.\"}],\"affected\":[{\"source\":\"disclosure@vulncheck.com\",\"affectedData\":[{\"vendor\":\"samanhappy\",\"product\":\"mcphub\",\"defaultStatus\":\"unaffected\",\"packageURL\":\"pkg:npm/%40samanhappy/mcphub\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"1.0.32\",\"versionType\":\"semver\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/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\",\"baseScore\":7.6,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"PASSIVE\",\"vulnConfidentialityImpact\":\"HIGH\",\"vulnIntegrityImpact\":\"HIGH\",\"vulnAvailabilityImpact\":\"NONE\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"cvssMetricV31\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N\",\"baseScore\":6.8,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":1.6,\"impactScore\":5.2}]},\"weaknesses\":[{\"source\":\"disclosure@vulncheck.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-287\"}]}],\"references\":[{\"url\":\"https://github.com/samanhappy/mcphub/blob/v1.0.31/src/services/oauthServerService.ts#L26-L38\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/samanhappy/mcphub/commit/e927620cd1a80e8691213b01eb8cd6ffa1a66e9f\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/samanhappy/mcphub/releases/tag/v1.0.32\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://github.com/samanhappy/mcphub/security/advisories/GHSA-3m7m-37xf-xp9x\",\"source\":\"disclosure@vulncheck.com\"},{\"url\":\"https://www.vulncheck.com/advisories/mcphub-before-1.0.32-oauth-2.0-authentication-bypass\",\"source\":\"disclosure@vulncheck.com\"}]}}"
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Loading…
Loading…