CVE-2019-5606 Use after free in FreeBSD
A use-after-free vulnerability in FreeBSD's posix_openpt handling allows local attackers to gain root privileges or escape jails.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2019-5606?
CVE-2019-5606 is a high-severity use after free vulnerability in Freebsd Freebsd, published on 26 Jul 2019. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In FreeBSD 12.0-STABLE before r349805, 12.0-RELEASE before 12.0-RELEASE-p8, 11.3-STABLE before r349806, 11.3-RELEASE before 11.3-RELEASE-p1, and 11.2-RELEASE before 11.2-RELEASE-p12, code which handles close of a descriptor created by posix_openpt fails to undo a signal configuration. This causes an incorrect signal to be raised leading to a write after free of kernel memory allowing a malicious user to gain root privileges or escape a jail.
Weakness: CWE-416
Which versions are affected by CVE-2019-5606?
It affects 1 product.
Products include Freebsd Freebsd.
How do I fix CVE-2019-5606?
No fix has been published for CVE-2019-5606 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2019-5606 being exploited?
There is no known exploitation of CVE-2019-5606 in the wild and no public exploit code.
Other vulnerabilities in Freebsd Freebsd
Sources
Also known as GHSA-42vr-5jh6-78jw.