High (7.8) in Microsoft Windows. In CISA KEV since 2022-06-14, with known ransomware use. EPSS 99% chance of exploitation in the next 30 days.
A remote code execution vulnerability exists when MSDT is called using the URL protocol from a calling application such as Word. An attacker who successfully exploits this vulnerability can run arbitrary code with the privileges of the calling application. The attacker can then install programs, view, change, or delete data, or create new accounts in the context allowed by the user’s rights.
Please see the MSRC Blog Entry for important information about steps you can take to protect your system from this vulnerability.
Severity
CVSS 3.1
7.8 high
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
99% chance of exploitation in the next 30 days; higher than 99% of CVEs (scores of 2026-10-31)
CISA KEV
listed 2022-06-14, due 2022-07-05, known ransomware use