USN-5259-1: Cron vulnerabilities

Related Vulnerabilities: CVE-2017-9525   CVE-2019-9704   CVE-2019-9705   CVE-2019-9706  

Several security issues were fixed in Cron.

It was discovered that Cron incorrectly handled user input during crontab file creation. An attacker could possibly use this issue to cause a denial of service. (CVE-2019-9705)

Details

It was discovered that the postinst maintainer script in Cron unsafely
handled file permissions during package install or update operations.
An attacker could possibly use this issue to perform a privilege
escalation attack. (CVE-2017-9525)

Florian Weimer discovered that Cron incorrectly handled certain memory
operations during crontab file creation. An attacker could possibly use
this issue to cause a denial of service. (CVE-2019-9704)

It was discovered that Cron incorrectly handled user input during crontab
file creation. An attacker could possibly use this issue to cause a denial
of service. (CVE-2019-9705)

It was discovered that Cron contained a use-after-free vulnerability in
its force_rescan_user function. An attacker could possibly use this issue
to cause a denial of service. (CVE-2019-9706)