Authorization bypass in OpenCSG CSGHub exposes private repo files
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-639.
Summary
OpenCSG CSGHub through v2.6.0-ce contains an authorization bypass (CWE-639) in its unauthenticated file resolve route. A remote attacker can read files from private model, code and space repositories without authentication, because the portal forwards the request with its server API key.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
OpenCSG CSGHub through v2.6.0-ce contains an authorization bypass vulnerability in the unauthenticated file resolve route that allows remote attackers to read private repository files. Attackers can inject a percent-encoded current_user parameter into the file path, which the portal forwards with its server API key, to read files in private model, code or space repositories.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
The sources list no fixed version for OpenCSG CSGHub.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Vendor assessments
Timeline
- 2026-11-02 Threatist record created from CVE-2026-120426
- 2026-11-02 Alias added: GHSA-p8qg-p5c7-m59c
- 2026-11-04 Priority changed: MEDIUM → LOW
- 2026-11-05 CISA SSVC decision points changed
- 2026-11-05 Priority changed: LOW → MEDIUM
- 2026-11-06 Affected versions changed · Red Hat
- 2026-11-06 CVSS score added · Red Hat
References
Other 7
- https://github.com/OpenCSGs/csghub/issues/1586
- https://github.com/OpenCSGs/csghub/blob/v2.6.0-ce/internal/routes/router.go#L302-L303
- https://github.com/OpenCSGs/csghub/blob/v2.6.0-ce/internal/handlers/frontend/resolve.go#L138-L151
- https://github.com/OpenCSGs/csghub/blob/v2.6.0-ce/pkg/server/backend/csghubserver/download.go#L10-L41
- https://github.com/OpenCSGs/csghub-server/blob/v2.6.0-ce/api/middleware/authenticator.go#L210-L226
- CSGHub v2.6.0-ce Release Notes
- https://hackmd.io/@hieund/csghub-private-repo-file-read-idor
Sources
- CVE-2026-120426 · CVE Program
- CVE-2026-120426 · NVD
- FIRST EPSS
- GHSA-p8qg-p5c7-m59c · GitHub Advisory Database · CC BY 4.0
- CVE-2026-120426 · Red Hat security data · CC BY 4.0
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