Advisoriesby IbisMicrosoftCVE-2026-40378
Microsoft Windows: excessive memory allocation
Fix: upgrade to 10.0.14393.9339 or later (10 fixed versions below)
Memory allocation with excessive size value in Windows Local Security Authority Subsystem Service (LSASS) allows an unauthorized attacker to deny service over a network.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Windows 10 Version 1607 Product | >= 10.0.14393.0, < 10.0.14393.9339 | 10.0.14393.9339 |
| Windows 10 Version 1809 Product | >= 10.0.17763.0, < 10.0.17763.9020 | 10.0.17763.9020 |
| Windows 10 Version 21H2 Product | >= 10.0.19044.0, < 10.0.19044.7548 | 10.0.19044.7548 |
| Windows 10 Version 22H2 Product | >= 10.0.19045.0, < 10.0.19045.7548 | 10.0.19045.7548 |
| Windows 11 Version 23H2 Product | >= 10.0.22631.0, < 10.0.22631.7376 | 10.0.22631.7376 |
| Windows 11 Version 24H2 Product | >= 10.0.26100.0, < 10.0.26100.8875 | 10.0.26100.8875 |
| Windows 11 Version 25H2 Product | >= 10.0.26200.0, < 10.0.26200.8875 | 10.0.26200.8875 |
| Windows 11 version 23H2 Product | >= 10.0.22631.0, < 10.0.22631.7376 | 10.0.22631.7376 |
| Windows 11 version 26H1 Product | >= 10.0.28000.0, < 10.0.28000.2525 | 10.0.28000.2525 |
| Windows Server 2012 Product | >= 6.2.9200.0, < 6.2.9200.26226 | 6.2.9200.26226 |
| Windows Server 2012 (Server Core installation) Product | >= 6.2.9200.0, < 6.2.9200.26226 | 6.2.9200.26226 |
| Windows Server 2012 R2 Product | >= 6.3.9600.0, < 6.3.9600.23291 | 6.3.9600.23291 |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-789