Ubuntu 16.04 LTS : Linux kernel vulnerabilities (USN-4419-1)

medium Nessus Plugin ID 138325

Synopsis

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

Description

The remote Ubuntu 16.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4419-1 advisory.

- There is a use-after-free in kernel versions before 5.5 due to a race condition between the release of ptp_clock and cdev while resource deallocation. When a (high privileged) process allocates a ptp device file (like /dev/ptpX) and voluntarily goes to sleep. During this time if the underlying device is removed, it can cause an exploitable condition as the process wakes up to terminate and clean all attached files.
The system crashes due to the cdev structure being invalid (as already freed) which is pointed to by the inode. (CVE-2020-10690)

- A NULL pointer dereference flaw was found in the Linux kernel's SELinux subsystem in versions before 5.7.
This flaw occurs while importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible bitmap via the' ebitmap_netlbl_import' routine. While processing the CIPSO restricted bitmap tag in the 'cipso_v4_parsetag_rbm' routine, it sets the security attribute to indicate that the category bitmap is present, even if it has not been allocated. This issue leads to a NULL pointer dereference issue while importing the same category bitmap into SELinux. This flaw allows a remote network user to crash the system kernel, resulting in a denial of service. (CVE-2020-10711)

- An issue was discovered in the Linux kernel through 5.6.11. sg_write lacks an sg_remove_request call in a certain failure case, aka CID-83c6f2390040. (CVE-2020-12770)

- gadget_dev_desc_UDC_store in drivers/usb/gadget/configfs.c in the Linux kernel 3.16 through 5.6.13 relies on kstrdup without considering the possibility of an internal '\0' value, which allows attackers to trigger an out-of-bounds read, aka CID-15753588bcd4. (CVE-2020-13143)

- ext4_protect_reserved_inode in fs/ext4/block_validity.c in the Linux kernel through 5.5.3 allows attackers to cause a denial of service (soft lockup) via a crafted journal size. (CVE-2020-8992)

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

Solution

Update the affected kernel package.

See Also

https://ubuntu.com/security/notices/USN-4419-1

Plugin Details

Severity: Medium

ID: 138325

File Name: ubuntu_USN-4419-1.nasl

Version: 1.7

Type: local

Agent: unix

Published: 7/9/2020

Updated: 1/9/2024

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2020-12770

CVSS v3

Risk Factor: Medium

Base Score: 6.7

Temporal Score: 5.8

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-1076-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-1110-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-1135-raspi2, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-1139-snapdragon, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-185-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-185-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-185-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-185-powerpc-e500mc, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-185-powerpc-smp, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-185-powerpc64-emb, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-185-powerpc64-smp, cpe:/o:canonical:ubuntu_linux:16.04:-:lts

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

Exploit Ease: No known exploits are available

Patch Publication Date: 7/6/2020

Vulnerability Publication Date: 2/14/2020

Reference Information

CVE: CVE-2020-10690, CVE-2020-10711, CVE-2020-12770, CVE-2020-13143, CVE-2020-8992

USN: 4419-1