CVE-2026-26128: Microsoft Windows 10 Version 1607 · Improper Authentication
Affects Microsoft Windows 10 Version 1607Source CVE Database V5
Not known to be exploited · CVSS 7.8 High : upgrade to 10.0.14393.8957 soon.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 50% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 10.0.14393.8957, 10.0.17763.8511, 10.0.19044.7058 +10
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CExploitation evidence
Disclosed: evidence found.
CVE published 10 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
Public exploit code: GitHub proofs of concept
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), GitHub proofs of concept, the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MicrosoftWindows 10 Version 1607 | Affected
| Fixed in
|
| MicrosoftWindows 10 Version 1809 | Affected
| Fixed in
|
| MicrosoftWindows 10 Version 21H2 | Affected
| Fixed in
|
| MicrosoftWindows 10 Version 22H2 | Affected
| Fixed in
|
| MicrosoftWindows 11 version 22H3 | Affected
| Fixed in
|
| MicrosoftWindows 11 Version 23H2 | Affected
| Fixed in
|
AI-suggested
An official fix is available from Microsoft for this vulnerability. Users and administrators should apply the security update provided by Microsoft as soon as possible to remediate the issue. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26128 for detailed patch information and deployment instructions.
Description
Improper authentication in Windows SMB Server allows an authorized attacker to elevate privileges locally.
References
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26128 (opens in a new tab)
- vicarius.io/vsociety/posts/cve-2026-26128-detection-script-improper-authentication-in-windows-smb-server (opens in a new tab)
- vicarius.io/vsociety/posts/cve-2026-26128-mitigation-script-improper-authentication-in-windows-smb-server (opens in a new tab)