CVE-2019-1064

CVE-2019-1064 is a high-severity (CVSS 7.8) vulnerability in Microsoft Windows. CISA added it to the Known Exploited Vulnerabilities catalog on March 15, 2022, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by April 5, 2022. CISA also lists it as known to be used in ransomware campaigns, so it should be prioritised accordingly. Microsoft has 390 vulnerabilities in the KEV catalog, 117 of them linked to ransomware.

An elevation of privilege vulnerability exists when Windows AppX Deployment Service (AppXSVC) improperly handles hard links. An attacker who successfully exploited this vulnerability could run processes in an elevated context. An attacker could then install programs; view, change or delete data. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take control of an affected system. The security update addresses the vulnerability by correcting how Windows AppX Deployment Service handles hard links.

CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1064
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1064
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-1064