CVE-2019-1253: Microsoft Windows AppX Deployment Server Privilege Escalation Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 15 Mar 2022, 916 days after the CVE record was published.

How likely is exploitation in the next 30 days?

11.6%

EPSS score, percentile 96 of all scored records

How severe?

7.8 High

CVSS v3.1 base score, from CISA's enrichment of the record

What should I do?

CISA deadline 5 Apr 2022. Apply updates per vendor instructions.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

• 10 Version 1703 for 32-bit Systems
• 10 Version 1703 for x64-based Systems
• 10 Version 1709 for 32-bit Systems
• 10 Version 1709 for x64-based Systems
• 10 Version 1803 for 32-bit Systems
• 10 Version 1803 for x64-based Systems

and 12 more in the table below

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 5 April 2022.

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

• https://nvd.nist.gov/vuln/detail/CVE-2019-1253

Affected products and versions

As listed in the CVE record.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

A privilege escalation vulnerability exists when the Windows AppX Deployment Server improperly handles junctions.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2019-1253 to its Known Exploited Vulnerabilities (KEV) catalog on 15 Mar 2022.
• CISA marks it as known to be used in ransomware campaigns.
• The due date CISA sets for the required action is 5 Apr 2022.
• The CVE record was published on 11 Sep 2019, 916 days before it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 7.8 (High), taken from CISA's enrichment of the record.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 11.6% (percentile 96), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

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.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-59: Improper Link Resolution Before File Access ('Link Following')

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

References

• portal.msrc.microsoft.com
• packetstormsecurity.com

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