Race condition in Linux kernel - CVE-2019-6974
Published: February 12, 2019 / Updated: May 30, 2020
Vulnerability identifier: #VU17555
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear
CVE-ID: CVE-2019-6974
CWE-ID: CWE-362
Exploitation vector: Adjecent network
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows an adjacent attacker to gain elevated privileges or cause a denial of service (DoS) condition.
The weakness exists due to exists due to a race condition that causes the kvm_ioctl_create_device function, as defined in the virt/kvm/kvm_main.c source code file of the affected software, to improperly handle reference counting. An adjacent attacker can access the system and execute an application that submits malicious input, trigger a use-after-free condition and cause a targeted guest virtual machine to crash, resulting in a DoS condition. In addition, a successful exploit could allow the attacker to gain elevated privileges on a targeted system.
The weakness exists due to exists due to a race condition that causes the kvm_ioctl_create_device function, as defined in the virt/kvm/kvm_main.c source code file of the affected software, to improperly handle reference counting. An adjacent attacker can access the system and execute an application that submits malicious input, trigger a use-after-free condition and cause a targeted guest virtual machine to crash, resulting in a DoS condition. In addition, a successful exploit could allow the attacker to gain elevated privileges on a targeted system.
How to mitigate CVE-2019-6974
The vulnerability has been addressed in the versions 4.9.156, 4.14.99, 4.19.21, 4.20.8.
Sources
- https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=cfa39381173d5f969daf43582c95ad679189cbc9
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.156
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.99
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.21
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.20.8
- https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.176