CVE-2019-1069

An elevation of privilege vulnerability exists in the way the Task Scheduler Service validates certain file operations. An attacker who successfully exploited the vulnerability could gain elevated privileges on a victim system. To exploit the vulnerability, an attacker would require unprivileged code execution on a victim system. The security update addresses the vulnerability by correctly validating file operations.

Weakness

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Software

Potential Mitigations

• Follow the principle of least privilege when assigning access rights to entities in a software system.
• Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/132.html
• https://cwe.mitre.org/data/definitions/17.html
• https://cwe.mitre.org/data/definitions/35.html
• https://cwe.mitre.org/data/definitions/76.html

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1069
• https://blog.0patch.com/2019/06/another-task-scheduler-0day-another.html
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1069
• https://www.kb.cert.org/vuls/id/119704
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-1069