CVE-2026-83646Active Directory Federation Services (AD FS) Spoofing Vulnerability
- 4.8MediumCVSS base score
- 0.37%Exploitation in 30 daysEPSS · top 68% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Url redirection to untrusted site ('open redirect') in Active Directory Federation Services (AD FS) allows an authorized attacker to perform spoofing over a network.
Timeline
ID reserved
By microsoft
- 43 days later
· 43 days later
Published
- 28 days later
· 28 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| microsoftCNA (assigner) | 3.1 | Medium4.8 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C |
| NVDNVD · Analyzed | 3.1 | Medium5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.37% · top 68% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.8.
Affected products
Microsoft · Windows 10 Version 1607
- affected 10.0.14393.0 – < 10.0.14393.9612
Microsoft · Windows 10 Version 1809
- affected 10.0.17763.0 – < 10.0.17763.9376
Microsoft · Windows Server 2016
- affected 10.0.14393.0 – < 10.0.14393.9612
Microsoft · Windows Server 2016 (Server Core installation)
- affected 10.0.14393.0 – < 10.0.14393.9612
Microsoft · Windows Server 2019
- affected 10.0.17763.0 – < 10.0.17763.9376
Microsoft · Windows Server 2019 (Server Core installation)
- affected 10.0.17763.0 – < 10.0.17763.9376
Microsoft · Windows Server 2022
- affected 10.0.20348.0 – < 10.0.20348.5761
Microsoft · Windows Server 2025
- affected 10.0.26100.0 – < 10.0.26100.33650
Microsoft · Windows Server 2025 (Server Core installation)
- affected 10.0.26100.0 – < 10.0.26100.33650
References
References1
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-99311 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-83646)Record last updated .