Vulnerability · Published Aug 11, 2026 · Assigned by microsoft
CVE-2026-62772Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability
High 7.8
In plain English
A high-severity heap buffer overflow in Windows 11 version 26H1 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities).
Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.3%top 73.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Heap-based buffer overflow in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 – before 10.0.28000.2704 |
Weakness: CWE-122 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C