USN-5259-2: Cron vulnerabilities
6 May 2022
Several security issues were fixed in Cron.
Releases
Packages
- cron - process scheduling daemon
Details
USN-5259-1 fixed several vulnerabilities in Cron. This update provides
the corresponding update for Ubuntu 18.04 LTS.
Original advisory 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)
Update instructions
The problem can be corrected by updating your system to the following package versions:
Ubuntu 18.04
In general, a standard system update will make all the necessary changes.