Ubuntu 16.04 LTS : Linux kernel vulnerabilities (USN-4708-1)

high Nessus Plugin ID 145510
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Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 16.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4708-1 advisory.

- An issue was discovered in fs/xfs/xfs_icache.c in the Linux kernel through 4.17.3. There is a NULL pointer dereference and panic in lookup_slow() on a NULL inode->i_ops pointer when doing pathwalks on a corrupted xfs image. This occurs because of a lack of proper validation that cached inodes are free during allocation. (CVE-2018-13093)

- In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image, performing some operations, and then making a syncfs system call can lead to a use-after-free in __mutex_lock in kernel/locking/mutex.c.
This is related to mutex_can_spin_on_owner in kernel/locking/mutex.c, __btrfs_qgroup_free_meta in fs/btrfs/qgroup.c, and btrfs_insert_delayed_items in fs/btrfs/delayed-inode.c. (CVE-2019-19813)

- In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image and performing some operations can cause slab-out-of-bounds write access in __btrfs_map_block in fs/btrfs/volumes.c, because a value of 1 for the number of data stripes is mishandled. (CVE-2019-19816)

- A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like local user could use this flaw to further increase their privileges to that of a running kernel. (CVE-2020-27777)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://ubuntu.com/security/notices/USN-4708-1

Plugin Details

Severity: High

ID: 145510

File Name: ubuntu_USN-4708-1.nasl

Version: 1.3

Type: local

Agent: unix

Published: 1/28/2021

Updated: 1/29/2021

Dependencies: ssh_get_info.nasl, linux_alt_patch_detect.nasl

Risk Information

CVSS Score Source: CVE-2019-19816

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 9.3

Temporal Score: 6.9

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

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:16.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-201-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-201-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-201-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-lts-utopic, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-lts-vivid, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-lts-wily, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-lts-xenial, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lts-utopic, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lts-vivid, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lts-wily, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lts-xenial, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-lts-utopic, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-lts-vivid, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-lts-wily, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-lts-xenial, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-lts-utopic, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-lts-vivid, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-lts-wily, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-lts-xenial

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 1/28/2021

Vulnerability Publication Date: 7/3/2018

Reference Information

CVE: CVE-2018-13093, CVE-2019-19813, CVE-2019-19816, CVE-2020-25669, CVE-2020-27777

BID: 104954

USN: 4708-1