CVE-2019-1253
Published: March 15, 2022
Official Description
A privilege escalation vulnerability exists when the Windows AppX Deployment Server improperly handles junctions.
CISA KEV Advisory
Microsoft Windows AppX Deployment Server Privilege Escalation Vulnerability
A privilege escalation vulnerability exists when the Windows AppX Deployment Server improperly handles junctions.
Apply updates per vendor instructions.
Risk Analysis
This vulnerability allows an attacker to gain elevated privileges on a Windows system due to how the AppX Deployment Server handles file system junctions. Its high severity and confirmed exploitation in the wild, along with an EPSS score of 0.30233, indicate a significant and active threat that requires immediate attention.
This flaw is actively being exploited in the wild, as confirmed by its presence in CISA's KEV catalog.
Apply the latest security updates for Windows to address the improper handling of junctions by the AppX Deployment Server. Ensure all system components are regularly patched to prevent privilege escalation.
Technical Analysis
CVE-2019-1253 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2019-1253 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2019-1253 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1