CVE-2026-65840
Fider: Cross-Tenant Authentication Bypass via Missing tenant_id Filter in getVerificationByKey
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
What each source reports
CVE List Score used 9.6
Fider: Cross-Tenant Authentication Bypass via Missing tenant_id Filter in getVerificationByKey
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.
- Record
CVE-2026-65840- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N - Weakness
- CWE-639
- Updated
- 2026-11-11
EUVDEUVD-2026-123702 9.6
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.
- Record
EUVD-2026-123702- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N - Updated
- 2026-11-11
NVD 9.6
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.
- Record
CVE-2026-65840- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N - Weakness
- CWE-639
- Updated
- 2026-11-11
OSV 9.6
Fider: Cross-Tenant Authentication Bypass via Missing tenant_id Filter in getVerificationByKey
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.
- Record
CVE-2026-65840- CVSS 3.1
- 9.6 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N - Weakness
- CWE-639
- Updated
- 2026-11-12
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, references | NVD, OSV | |
| cwes, references, severity, title | CVE List | |
| first indexed | EUVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-65840 is a critical vulnerability (CVSS 9.6) in Getfider Fider, published November 11, 2026. No source lists public exploit code. No source names a fixed version.