CVE-2018-8340
A security feature bypass vulnerability exists when Active Directory Federation Services (AD FS) improperly handles multi-factor authentication requests, aka "AD FS Security Feature Bypass Vulnerability." This affects Windows Server 2016, Windows Server…
Does this matter?
Lower severity and a low EPSS score (7.89%). Track it; it rarely justifies an emergency change on its own.
Description
A security feature bypass vulnerability exists when Active Directory Federation Services (AD FS) improperly handles multi-factor authentication requests, aka "AD FS Security Feature Bypass Vulnerability." This affects Windows Server 2016, Windows Server 2012 R2, Windows 10 Servers.
- CVSS 3.0
- 6.5 MEDIUMCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 7.89% probability · 95th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- microsoft/windows server 2012 · microsoft/windows server 2016
- Source
- secure@microsoft.com
EPSS 7.9% since 27 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/105029Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1041474Third Party Advisory, VDB Entry
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8340Patch, Vendor Advisory
- http://www.securityfocus.com/bid/105029Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1041474Third Party Advisory, VDB Entry
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8340Patch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.