Windows 10 Version 1607: Integer Underflow (Wrap or Wraparound)
CVE-2026-54982 is a high-severity integer underflow (wrap or wraparound) vulnerability in Windows 10 Version 1607 from Microsoft, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists version 10.0.14393.9339 as the first without the flaw, so updating Windows 10 Version 1607 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.53% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Windows 10 Version 1607 to 10.0.14393.9339 or a later version.
- Update Windows 10 Version 1809 to 10.0.17763.9020 or a later version.
- Update Windows 10 Version 21H2 to 10.0.19044.7548 or a later version.
- Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Microsoft | Windows 10 Version 1607 | 10.0.14393.0 up to, but not including, 10.0.14393.9339 | 10.0.14393.9339 |
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 up to, but not including, 10.0.17763.9020 | 10.0.17763.9020 |
| Microsoft | Windows 10 Version 21H2 | 10.0.19044.0 up to, but not including, 10.0.19044.7548 | 10.0.19044.7548 |
| Microsoft | Windows 10 Version 22H2 | 10.0.19045.0 up to, but not including, 10.0.19045.7548 | 10.0.19045.7548 |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 up to, but not including, 10.0.26100.8875 | 10.0.26100.8875 |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 up to, but not including, 10.0.26200.8875 | 10.0.26200.8875 |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 up to, but not including, 10.0.28000.2525 | 10.0.28000.2525 |
| Microsoft | Windows Server 2012 | 6.2.9200.0 up to, but not including, 6.2.9200.26226 | 6.2.9200.26226 |
| Microsoft | Windows Server 2012 (Server Core installation) | 6.2.9200.0 up to, but not including, 6.2.9200.26226 | 6.2.9200.26226 |
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 up to, but not including, 6.3.9600.23291 | 6.3.9600.23291 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 up to, but not including, 6.3.9600.23291 | 6.3.9600.23291 |
| Microsoft | Windows Server 2016 | 10.0.14393.0 up to, but not including, 10.0.14393.9339 | 10.0.14393.9339 |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 up to, but not including, 10.0.14393.9339 | 10.0.14393.9339 |
| Microsoft | Windows Server 2019 | 10.0.17763.0 up to, but not including, 10.0.17763.9020 | 10.0.17763.9020 |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 up to, but not including, 10.0.17763.9020 | 10.0.17763.9020 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 up to, but not including, 10.0.20348.5386 | 10.0.20348.5386 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 up to, but not including, 10.0.26100.33158 | 10.0.26100.33158 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 up to, but not including, 10.0.26100.33158 | 10.0.26100.33158 |
| Microsoft | Windows 10 1607 | before 10.0.14393.9339 | 10.0.14393.9339 |
| Microsoft | Windows 10 1809 | before 10.0.17763.9020 | 10.0.17763.9020 |
| Microsoft | Windows 10 21h2 | before 10.0.19044.7548 | 10.0.19044.7548 |
| Microsoft | Windows 10 22h2 | before 10.0.19045.7548 | 10.0.19045.7548 |
| Microsoft | Windows 11 24h2 | before 10.0.26100.8875 | 10.0.26100.8875 |
| Microsoft | Windows 11 25h2 | before 10.0.26200.8875 | 10.0.26200.8875 |
| Microsoft | Windows 11 26h1 | before 10.0.28000.2525 | 10.0.28000.2525 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (microsoft.com).
Official description
Integer underflow (wrap or wraparound) in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over an adjacent network.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Integer Underflow (Wrap or Wraparound)
The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
More Integer Underflow (Wrap or Wraparound) vulnerabilities (CWE-191)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Recent Integer Underflow (Wrap or Wraparound) vulnerabilities
- 9.8 Critical severity
- 7.5 High severity
- 9.1 Critical severity
- 7.1 High severity
- 8.1 High severity
- 9.8 Critical severity
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