What’s Vulnerable › Vulnerabilities

CVE-2026-103396: bbs-go through 4.4.6 Incorrect Authorization via /api/admin/user/synccount

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-30 · updated 2026-09-30
• Weakness: CWE-863

Description

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.

Affected products

• mlogclub bbs-go: through 4.4.6

References

• 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

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