CVE-2019-19448

2019-12-0800:00:00

ubuntu.com

7.8 High

CVSS3

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

6.8 Medium

CVSS2

Access Vector

NETWORK

Access Complexity

MEDIUM

Authentication

NONE

Confidentiality Impact

PARTIAL

Integrity Impact

PARTIAL

Availability Impact

PARTIAL

AV:N/AC:M/Au:N/C:P/I:P/A:P

0.001 Low

EPSS

Percentile

45.5%

JSON

In the Linux kernel 5.0.21 and 5.3.11, mounting a crafted btrfs filesystem
image, performing some operations, and then making a syncfs system call can
lead to a use-after-free in try_merge_free_space in
fs/btrfs/free-space-cache.c because the pointer to a left data structure
can be the same as the pointer to a right data structure.

Bugs

<https://bugzilla.suse.com/show_bug.cgi?id=1158820>

Notes

Author	Note
tyhicks	Exploiting this vulnerability requires a crafted filesystem image to be mounted
sbeattie	it’s asserted that the btrfs enhanced tree-checker should address this issue; this was backported to at least the 4.15 kernels.

OSVersionArchitecturePackageVersionFilename
ubuntu16.04noarchlinux-hwe< 4.15.0-120.122~16.04.1UNKNOWN
ubuntu18.04noarchlinux< 4.15.0-121.123UNKNOWN
ubuntu20.04noarchlinux< 5.4.0-48.52UNKNOWN
ubuntu16.04noarchlinux< 4.4.0-190.220UNKNOWN
ubuntu14.04noarchlinux-aws< 4.4.0-1078.82) Available with Ubuntu Pro or Ubuntu Pro (Infra-onlyUNKNOWN
ubuntu20.04noarchlinux-aws< 5.4.0-1025.25UNKNOWN
ubuntu18.04noarchlinux-aws< 4.15.0-1086.91UNKNOWN
ubuntu16.04noarchlinux-aws< 4.4.0-1114.127UNKNOWN
ubuntu16.04noarchlinux-aws-hwe< 4.15.0-1085.90~16.04.1UNKNOWN
ubuntu20.04noarchlinux-azure< 5.4.0-1026.26UNKNOWN

OS	Version	Architecture	Package	Version	Filename
ubuntu	16.04	noarch	linux-hwe	< 4.15.0-120.122~16.04.1	UNKNOWN
ubuntu	18.04	noarch	linux	< 4.15.0-121.123	UNKNOWN
ubuntu	20.04	noarch	linux	< 5.4.0-48.52	UNKNOWN
ubuntu	16.04	noarch	linux	< 4.4.0-190.220	UNKNOWN
ubuntu	14.04	noarch	linux-aws	< 4.4.0-1078.82) Available with Ubuntu Pro or Ubuntu Pro (Infra-only	UNKNOWN
ubuntu	20.04	noarch	linux-aws	< 5.4.0-1025.25	UNKNOWN
ubuntu	18.04	noarch	linux-aws	< 4.15.0-1086.91	UNKNOWN
ubuntu	16.04	noarch	linux-aws	< 4.4.0-1114.127	UNKNOWN
ubuntu	16.04	noarch	linux-aws-hwe	< 4.15.0-1085.90~16.04.1	UNKNOWN
ubuntu	20.04	noarch	linux-azure	< 5.4.0-1026.26	UNKNOWN