CVE-2019-1253 — Microsoft
HIGHCVE-2019-1253 is a high-severity (CVSS 7.8) CWE-59 vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-15) and has been used in ransomware campaigns — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.
An elevation of privilege vulnerability exists when the Windows AppX Deployment Server improperly handles junctions.To exploit this vulnerability, an attacker would first have to gain…
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2022-03-15 — including use in ransomware campaigns. Federal agencies were required to remediate by 2022-04-05.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2019-1253.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2019-1253 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 395,308 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Counts from FIRST.org, log-scaled.
Description
An elevation of privilege vulnerability exists when the Windows AppX Deployment Server improperly handles junctions.To exploit this vulnerability, an attacker would first have to gain execution on the victim system, aka 'Windows Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-1215, CVE-2019-1278, CVE-2019-1303.
Affected Products
windows 10 1703microsoftwindows 10 1709microsoftwindows 10 1803microsoftwindows 10 1809microsoftwindows 10 1903microsoftwindows server 1803microsoftResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
AppXSvc - Privilege Escalation
by Gabor Seljan · Sep 16, 2019
Detection & mitigation playbook
VulnerabilityDetect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
No fixed release is recorded for CVE-2019-1253 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2019-1253 in your dependencies?
Find it across , including transitive dependencies.