NVD / CVE Program· CNA VulnCheck

CVE-2026-90474: MCPHub before 1.0.32 OAuth 2.0 Authentication Bypass

Noroxi assessment

Priority: Monitor (action score 30/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.55% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. No account or password is required. No special conditions are required; it is repeatable.
Fixed version: samanhappy mcphub 1.0.32.

Low priority for now. Upgrade to samanhappy mcphub 1.0.32 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

HighCVSS 7.6 · v4.0—No exploit Fix available

EUVD-2026-76850

Published: Sep 12, 2026
Updated: Sep 24, 2026
EPSS: 0.5% · 45th percentile
CWE: CWE-287

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.6 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.5%

CISA SSVC decision

Exploitation: proof of concept
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · VulnCheck: 7.6; NVD has not scored this yet; the score shown is the CNA’s.

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

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (VulnCheck). Independent of NVD's CPE analysis and usually ahead of it.

samanhappy mcphub
- before 1.0.32affected · semver

Same product

samanhappy: all records

Other highest-scoring records for the same primary product.

CVE-2026-79748MCPHub: Authenticated non-admin user achieves RCE via POST /api/servers (missing authorization on stdio command/args)
39Monitor
CVE-2026-79744MCPHub: Missing Authorization on `PUT /api/system-config` Lets Any Non-Admin Rewrite Global Security Configuration
35Monitor
CVE-2026-79746MCPHub: Server-scoped bearer key gains access to an entire group via partial (any-overlap) server matching
32Monitor

Published before and after this one in the same product

← EarlierCVE-2026-79749Aug 31, 2026 · MCPHub: SSRF Guard Bypass via IPv6 Transition Addresses in URL Validation
30Monitor
← EarlierCVE-2026-79750Aug 31, 2026 · MCPHub authenticated horizontal IDOR: any non-admin user executes tools on other users' MCP servers (cross-tenant file read + SSRF)
30Monitor
Later →CVE-2026-94047Sep 20, 2026 · samanhappy MCPHub Template Import Endpoint templateService.ts importTemplate privileges management
8Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
samanhappy mcphub	1.0.32	Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

samanhappy/mcphubcommit e927620

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Wayde Shi (PayPal Cyber Security Team)finder

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

—

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

CVE-2026-7974812 days apartMCPHub: Authenticated non-admin user achieves RCE via POST /api/servers (missing authorization on stdio command/args)
39Monitor
CVE-2026-7974912 days apartMCPHub: SSRF Guard Bypass via IPv6 Transition Addresses in URL Validation
30Monitor
CVE-2026-7975012 days apartMCPHub authenticated horizontal IDOR: any non-admin user executes tools on other users' MCP servers (cross-tenant file read + SSRF)
30Monitor
CVE-2026-7974712 days apartMCPHub vulnerable to SSRF: a non-admin user can make mcphub request arbitrary URLs and read the response (OpenAPI proxy + transport dial)
28Monitor

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: P
Scope: X

Weakness class (CWE)

CWE-287 · Improper Authentication

CVSS vector

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

nvd-secondary

Root cause

Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.

The bug in code

The whole CWE-287 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1app.use("/admin", requireSession, adminRouter);
2

3// Route added later skips the middleware
4app.post("/admin-api/config", updateConfig);

Fixed

1const admin = express.Router();
2admin.use(requireSession, requireRole("admin"));
3

4admin.post("/config", updateConfig);
5app.use("/admin", admin);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

Change log

Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

For records you follow, these changes also arrive as notifications. →

References

github.com/samanhappy/mcphub/blob/v1.0.31/src/services/oauthServerService.ts#L26-L38

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records