CVE-2026-103396

bbs-go through 4.4.6 contains a permission bypass vulnerability in the AdminMiddleware authorization logic where the read-only dashboard.user.view permission rule matches the /api/admin/user/synccount endpoint before the intended dashboard.user.update rule. Authenticated users with only view permissions can call the synccount endpoint to trigger expensive full-table user recounts and cache invalidations, causing denial of service through repeated concurrent database operations.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/mlogclub/bbs-go
https://github.com/mlogclub/bbs-go/blob/v4.4.6/internal/handlers/admin/user_handlers.go#L47-L59
https://github.com/mlogclub/bbs-go/blob/v4.4.6/internal/permissions/admin_permission_registry.go#L59-L60
https://github.com/mlogclub/bbs-go/commit/97d0bb3dcbacd686fd5300295afbf4f4a5da7609
https://github.com/mlogclub/bbs-go/issues/303
https://www.vulncheck.com/advisories/bbs-go-through-4.4.6-incorrect-authorization-via-api-admin-user-synccount

Configurations

No configuration.

History

30 Sep 2026, 15:22

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 15:22

Updated : 2026-09-30 17:32

NVD link : CVE-2026-103396

Mitre link : CVE-2026-103396

CVE.ORG link : CVE-2026-103396

JSON object : View

Products Affected

No product.

CWE

CWE-863

Incorrect Authorization

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