CVE-2026-79746 (GCVE-0-2026-79746)
Vulnerability from cvelistv5 – Published: 2026-08-31 17:55 – Updated: 2026-09-01 14:59
VLAI
EPSS
VEX
Title
MCPHub: Server-scoped bearer key gains access to an entire group via partial (any-overlap) server matching
Summary
MCPHub is a unified hub for centrally managing and dynamically orchestrating multiple MCP servers/APIs into separate endpoints with flexible routing strategies. Prior to version 1.0.31, when a bearer key with accessType: 'servers' (or 'custom') is used against a group route, isBearerKeyAllowedForRequest grants access to the entire group as long as any single server in that group appears in the key's allowedServers list — not only when every server the key is scoped to matches, and critically, without ever re-checking allowedServers again once the group-level connection is authorized. A key explicitly scoped to one specific server therefore also grants full access to every other server that happens to share a group with it, including servers the key was never authorized for. This issue has been patched in version 1.0.31.
Severity
8.1 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-01 14:16 UTC
CWE
- CWE-863 - Incorrect Authorization
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/samanhappy/mcphub/security/adv… | x_refsource_CONFIRM |
| https://github.com/samanhappy/mcphub/pull/1059 | x_refsource_MISC |
| https://github.com/samanhappy/mcphub/commit/2b10a… | x_refsource_MISC |
| https://github.com/samanhappy/mcphub/releases/tag… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| samanhappy | mcphub |
Affected:
< 1.0.31
|
guessed |
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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.
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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.
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