Vulnerability · Published Sep 8, 2026 · Assigned by microsoft
CVE-2026-69530Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability
High 8.1
In plain English
A high-severity use-after-free in Windows 10 Version 1809 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 54% of all known vulnerabilities).
Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.7%top 46.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Use after free in Reliable Multicast Transport Driver (RMCAST) allows an unauthorized attacker to execute code over a network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2019 | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 – before 10.0.17763.9245 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 – before 10.0.20348.5622 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – before 10.0.26100.33438 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – before 10.0.26100.33438 |
Weakness: CWE-416 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
References
- Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability vendor-advisory, patch