CVE-2026-83656
Microsoft Windows 10 21h2: missing authentication
- Risk score
- 42/100
- CVSS
- 4.7 v3.1
- Exploit chance (30 days)
- 0.3%
- Published
- 13 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Missing authentication for critical function in Windows Modern Device Management (MDM) allows an authorized attacker to perform tampering locally.
- Affected
- Microsoft Windows 10 21h2
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Story map
At a glance
Microsoft Windows 10 21h2: Amber, patch this week. Out-of-bounds write in Microsoft Windows PDF allows an unauthorized attacker to execute code over a network.
The flaws
- CVE-2026-83656: Missing authentication (CVSS 4.7 · EPSS 0%)
- CVE-2026-108457: Out-of-bounds write (CVSS 8.1 · EPSS 1%)
- CVE-2026-85369: Out-of-bounds read (CVSS 8.8 · EPSS 0%)
- CVE-2026-105733: Incorrect authorisation (CVSS 8.8 · EPSS 0%)
The fix
Fix: Apply the vendor's security update; see the linked advisory.
Who is exposed: Microsoft Windows 10 21h2
Where it stands
- No known exploitation
Connects to
- Same weakness: Missing authentication (CWE-306). 351 other warnings in 30 days
- Same product: Earlier Microsoft Windows 10 21h2 warnings. 55 in the last 90 days
Why it is Yellow
- CVSS 4.7 medium
- On your watchlist: windows server
References
Original description
Missing authentication for critical function in Windows Modern Device Management (MDM) allows an authorized attacker to perform tampering locally.
Last activity 13 Oct 2026. Patch Forecast updates every hour.