CVSS 3.1
9.6 criticalCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:NCVE-2026-65840 Fider: Cross-Tenant Authentication Bypass via Missing tenant_id Filter in getVerificationByKey
Critical (9.6) in getfider fider. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.
Fider is a feedback portal for feature requests and suggestions. Prior to version 0.36.0, in multi-tenant mode (HOST_MODE=multi), an attacker can use an email verification key issued by Tenant A to authenticate as the same email address on Tenant B. This completely bypasses tenant isolation and allows unauthorized account takeover across tenants. Single-host deployments (HOST_MODE=single, the default) are NOT affected. This issue has been patched in version 0.36.0.
Severity
- EPSS
- 0.3% estimated probability of exploitation activity in the next 30 days; 23rd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: total, assessed 2026-11-12. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-639 Authorization Bypass Through User-Controlled Key
- OWASP Top 10
- A01:2025 Broken Access Control
- Published
- Modified
- Assigned by
- GitHub_M (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| getfider fider | < 0.36.0 |
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.