Use after free in Linux kernel - CVE-2019-19318

Vulnerability identifier: #VU92777

CSH Severity: Low

CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2019-19318

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local privileged user to perform a denial of service (DoS) attack.

In the Linux kernel 5.3.11, mounting a crafted btrfs image twice can cause an rwsem_down_write_slowpath use-after-free because (in rwsem_can_spin_on_owner in kernel/locking/rwsem.c) rwsem_owner_flags returns an already freed pointer,

Linux kernel
Ubuntu
linux-image-4.15.0-107-lowlatency (Ubuntu package)
linux-image-4.15.0-107-generic-lpae (Ubuntu package)
linux-image-4.15.0-107-generic (Ubuntu package)
linux-image-virtual-hwe-16.04 (Ubuntu package)
linux-image-lowlatency-hwe-16.04 (Ubuntu package)
linux-image-generic-lpae-hwe-16.04 (Ubuntu package)
linux-image-generic-hwe-16.04 (Ubuntu package)
linux-image-oem (Ubuntu package)
linux-image-generic-lpae (Ubuntu package)
linux-image-generic (Ubuntu package)
linux-image-lowlatency (Ubuntu package)
linux-image-virtual (Ubuntu package)
linux-image-4.15.0-109-lowlatency (Ubuntu package)
linux-image-4.15.0-109-generic-lpae (Ubuntu package)
linux-image-4.15.0-109-generic (Ubuntu package)
linux-image-oracle (Ubuntu package)
linux-image-4.15.0-1046-oracle (Ubuntu package)
linux-image-4.15.0-1048-oracle (Ubuntu package)
linux-image-oracle-lts-18.04 (Ubuntu package)
linux-image-gke-4.15 (Ubuntu package)
linux-image-gke (Ubuntu package)
linux-image-4.15.0-1064-gke (Ubuntu package)
linux-image-raspi2 (Ubuntu package)
linux-image-4.15.0-1065-raspi2 (Ubuntu package)
linux-image-kvm (Ubuntu package)
linux-image-4.15.0-1069-kvm (Ubuntu package)
linux-image-aws-hwe (Ubuntu package)
linux-image-4.15.0-1074-aws (Ubuntu package)
linux-image-aws-lts-18.04 (Ubuntu package)
linux-image-4.15.0-1077-aws (Ubuntu package)
linux-image-gcp (Ubuntu package)
linux-image-4.15.0-1078-gcp (Ubuntu package)
linux-image-gcp-lts-18.04 (Ubuntu package)
linux-image-snapdragon (Ubuntu package)
linux-image-4.15.0-1081-snapdragon (Ubuntu package)
linux-image-azure-lts-18.04 (Ubuntu package)
linux-image-azure (Ubuntu package)
linux-image-4.15.0-1091-azure (Ubuntu package)
linux-image-4.15.0-1091-oem (Ubuntu package)

Install update from vendor's repository.

linux-image-4.15.0-107-lowlatency (Ubuntu package) - update to 4.15.0-107.108~16.04.1
linux-image-4.15.0-107-generic-lpae (Ubuntu package) - update to 4.15.0-107.108~16.04.1
linux-image-4.15.0-107-generic (Ubuntu package) - update to 4.15.0-107.108~16.04.1
linux-image-virtual-hwe-16.04 (Ubuntu package) - update to 4.15.0.107.112
linux-image-lowlatency-hwe-16.04 (Ubuntu package) - update to 4.15.0.107.112
linux-image-generic-lpae-hwe-16.04 (Ubuntu package) - update to 4.15.0.107.112
linux-image-generic-hwe-16.04 (Ubuntu package) - update to 4.15.0.107.112
linux-image-oem (Ubuntu package) - addressed in versions 4.15.0.107.112, 4.15.0.1091.94
linux-image-generic-lpae (Ubuntu package) - update to 4.15.0.109.97
linux-image-generic (Ubuntu package) - update to 4.15.0.109.97
linux-image-lowlatency (Ubuntu package) - update to 4.15.0.109.97
linux-image-virtual (Ubuntu package) - update to 4.15.0.109.97
linux-image-4.15.0-109-lowlatency (Ubuntu package) - update to 4.15.0-109.110
linux-image-4.15.0-109-generic-lpae (Ubuntu package) - update to 4.15.0-109.110
linux-image-4.15.0-109-generic (Ubuntu package) - update to 4.15.0-109.110
linux-image-oracle (Ubuntu package) - update to 4.15.0.1046.39
linux-image-4.15.0-1046-oracle (Ubuntu package) - update to 4.15.0-1046.50~16.04.1
linux-image-4.15.0-1048-oracle (Ubuntu package) - update to 4.15.0-1048.52
linux-image-oracle-lts-18.04 (Ubuntu package) - update to 4.15.0.1048.57
linux-image-gke-4.15 (Ubuntu package) - update to 4.15.0.1064.66
linux-image-gke (Ubuntu package) - addressed in versions 4.15.0.1064.66, 4.15.0.1078.80
linux-image-4.15.0-1064-gke (Ubuntu package) - update to 4.15.0-1064.67
linux-image-raspi2 (Ubuntu package) - update to 4.15.0.1065.63
linux-image-4.15.0-1065-raspi2 (Ubuntu package) - update to 4.15.0-1065.69
linux-image-kvm (Ubuntu package) - update to 4.15.0.1069.65
linux-image-4.15.0-1069-kvm (Ubuntu package) - update to 4.15.0-1069.70
linux-image-aws-hwe (Ubuntu package) - update to 4.15.0.1074.74
linux-image-4.15.0-1074-aws (Ubuntu package) - update to 4.15.0-1074.78~16.04.1
linux-image-aws-lts-18.04 (Ubuntu package) - update to 4.15.0.1077.79
linux-image-4.15.0-1077-aws (Ubuntu package) - update to 4.15.0-1077.81
linux-image-gcp (Ubuntu package) - update to 4.15.0.1078.80
linux-image-4.15.0-1078-gcp (Ubuntu package) - addressed in versions 4.15.0-1078.88, 4.15.0-1078.88~16.04.1
linux-image-gcp-lts-18.04 (Ubuntu package) - update to 4.15.0.1078.94
linux-image-snapdragon (Ubuntu package) - update to 4.15.0.1081.84
linux-image-4.15.0-1081-snapdragon (Ubuntu package) - update to 4.15.0-1081.88
linux-image-azure-lts-18.04 (Ubuntu package) - update to 4.15.0.1091.62
linux-image-azure (Ubuntu package) - addressed in versions 4.15.0.1091.68, 4.15.0.1091.86
linux-image-4.15.0-1091-azure (Ubuntu package) - addressed in versions 4.15.0-1091.101, 4.15.0-1091.101~14.04.1, 4.15.0-1091.101~16.04.1
linux-image-4.15.0-1091-oem (Ubuntu package) - update to 4.15.0-1091.101

• http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00021.html
• https://github.com/bobfuzzer/CVE/tree/master/CVE-2019-19318
• https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
• https://security.netapp.com/advisory/ntap-20200103-0001/
• https://usn.ubuntu.com/4414-1/

• Use after free in Linux kernel
• Ubuntu update for linux