CVE-2026-103396 json
bbs-go through 4.4.6 Incorrect Authorization via /api/admin/user/synccount
published last mo. modified last mo. also EUVD-2026-89991
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
Is CVE-2026-103396 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/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 |
Affected products
- mlogclub bbs-go
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/mlogclub/bbs-go/commit/97d0bb3dcbacd686fd5300295afbf4f4a5da7609
patch
-
github.com
/mlogclub/bbs-go/issues/303
issue-tracking
-
github.com
/mlogclub/bbs-go/blob/v4.4.6/internal/permissions/admin_permission_registry.go#L59-L60
technical-description
-
github.com
/mlogclub/bbs-go/blob/v4.4.6/internal/handlers/admin/user_handlers.go#L47-L59
technical-description
-
github.com
/mlogclub/bbs-go
product
-
vulncheck.com
/advisories/bbs-go-through-4.4.6-incorrect-authorization-via-api-admin-user-synccount
third-party-advisory
Sources
- CVE List CVE-2026-103396
- NVD CVE-2026-103396
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.