CVE-2019-18683 Use after free in n/a
Local attackers can exploit race conditions in the vivid driver to trigger a use-after-free, leading to privilege escalation on systems with the driver loaded.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2019-18683?
CVE-2019-18683 is a high-severity use after free vulnerability in Broadcom Fabric Operating System, published on 4 Nov 2019. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An issue was discovered in drivers/media/platform/vivid in the Linux kernel through 5.3.8. It is exploitable for privilege escalation on some Linux distributions where local users have /dev/video0 access, but only if the driver happens to be loaded. There are multiple race conditions during streaming stopping in this driver (part of the V4L2 subsystem). These issues are caused by wrong mutex locking in vivid_stop_generating_vid_cap(), vivid_stop_generating_vid_out(), sdr_cap_stop_streaming(), and the corresponding kthreads. At least one of these race conditions leads to a use-after-free.
Which versions are affected by CVE-2019-18683?
It affects 18 products.
Products include Broadcom Fabric Operating System, Canonical Ubuntu Linux, Debian Debian Linux, Linux kernel, Netapp 8300 Firmware, Netapp 8700 Firmware and 12 more.
How do I fix CVE-2019-18683?
Apply the vendor's patch.
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-2019-18683 being exploited?
There is no known exploitation of CVE-2019-18683 in the wild and no public exploit code.
Public exploit code: 2 proofs of concept on GitHub.
Other vulnerabilities in Broadcom Fabric Operating System
Sources
Also known as DEBIAN-CVE-2019-18683, GHSA-fgwh-54wv-865r, UBUNTU-CVE-2019-18683.