Ubuntu 20.04 LTS : Linux kernel (OEM) vulnerabilities (USN-4752-1)

high Nessus Plugin ID 147982
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

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

Description

The remote Ubuntu 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4752-1 advisory.

- Legacy pairing and secure-connections pairing authentication in Bluetooth BR/EDR Core Specification v5.2 and earlier may allow an unauthenticated user to complete authentication without pairing credentials via adjacent access. An unauthenticated, adjacent attacker could impersonate a Bluetooth BR/EDR master or slave to pair with a previously paired remote device to successfully complete the authentication procedure without knowing the link key. (CVE-2020-10135)

- A memory out-of-bounds read flaw was found in the Linux kernel before 5.9-rc2 with the ext3/ext4 file system, in the way it accesses a directory with broken indexing. This flaw allows a local user to crash the system if the directory exists. The highest threat from this vulnerability is to system availability.
(CVE-2020-14314)

- Use-after-free vulnerability in fs/block_dev.c in the Linux kernel before 5.8 allows local users to gain privileges or cause a denial of service by leveraging improper access to a certain error field.
(CVE-2020-15436)

- The Linux kernel before version 5.8 is vulnerable to a NULL pointer dereference in drivers/tty/serial/8250/8250_core.c:serial8250_isa_init_ports() that allows local users to cause a denial of service by using the p->serial_in pointer which uninitialized. (CVE-2020-15437)

- Improper buffer restrictions in BlueZ may allow an unauthenticated user to potentially enable denial of service via adjacent access. This affects all Linux kernel versions that support BlueZ. (CVE-2020-24490)

- A TOCTOU mismatch in the NFS client code in the Linux kernel before 5.8.3 could be used by local attackers to corrupt memory or possibly have unspecified other impact because a size check is in fs/nfs/nfs4proc.c instead of fs/nfs/nfs4xdr.c, aka CID-b4487b935452. (CVE-2020-25212)

- The rbd block device driver in drivers/block/rbd.c in the Linux kernel through 5.8.9 used incomplete permission checking for access to rbd devices, which could be leveraged by local attackers to map or unmap rbd block devices, aka CID-f44d04e696fe. (CVE-2020-25284)

- A flaw was found in the Linux kernel's implementation of biovecs in versions before 5.9-rc7. A zero-length biovec request issued by the block subsystem could cause the kernel to enter an infinite loop, causing a denial of service. This flaw allows a local attacker with basic privileges to issue requests to a block device, resulting in a denial of service. The highest threat from this vulnerability is to system availability. (CVE-2020-25641)

- A flaw was found in the HDLC_PPP module of the Linux kernel in versions before 5.9-rc7. Memory corruption and a read overflow is caused by improper input validation in the ppp_cp_parse_cr function which can cause the system to crash or cause a denial of service. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. (CVE-2020-25643)

- A flaw memory leak in the Linux kernel performance monitoring subsystem was found in the way if using PERF_EVENT_IOC_SET_FILTER. A local user could use this flaw to starve the resources causing denial of service. (CVE-2020-25704)

- An issue was discovered in ioapic_lazy_update_eoi in arch/x86/kvm/ioapic.c in the Linux kernel before 5.9.2. It has an infinite loop related to improper interaction between a resampler and edge triggering, aka CID-77377064c3a9. (CVE-2020-27152)

- A buffer over-read (at the framebuffer layer) in the fbcon code in the Linux kernel before 5.8.15 could be used by local attackers to read kernel memory, aka CID-6735b4632def. (CVE-2020-28915)

- An issue was discovered in __split_huge_pmd in mm/huge_memory.c in the Linux kernel before 5.7.5. The copy-on-write implementation can grant unintended write access because of a race condition in a THP mapcount check, aka CID-c444eb564fb1. (CVE-2020-29368)

- An issue was discovered in mm/mmap.c in the Linux kernel before 5.7.11. There is a race condition between certain expand functions (expand_downwards and expand_upwards) and page-table free operations from an munmap call, aka CID-246c320a8cfe. (CVE-2020-29369)

- An issue was discovered in romfs_dev_read in fs/romfs/storage.c in the Linux kernel before 5.8.4.
Uninitialized memory leaks to userspace, aka CID-bcf85fcedfdd. (CVE-2020-29371)

- A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13.
drivers/tty/tty_io.c and drivers/tty/tty_jobctrl.c may allow a read-after-free attack against TIOCGSID, aka CID-c8bcd9c5be24. (CVE-2020-29660)

- A locking issue was discovered in the tty subsystem of the Linux kernel through 5.9.13.
drivers/tty/tty_jobctrl.c allows a use-after-free attack against TIOCSPGRP, aka CID-54ffccbf053b.
(CVE-2020-29661)

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 linux-image-5.6.0-1048-oem and / or linux-image-oem-20.04 packages.

See Also

https://ubuntu.com/security/notices/USN-4752-1

Plugin Details

Severity: High

ID: 147982

File Name: ubuntu_USN-4752-1.nasl

Version: 1.3

Type: local

Agent: unix

Published: 3/23/2021

Updated: 3/24/2021

Dependencies: ssh_get_info.nasl, linux_alt_patch_detect.nasl

Risk Information

CVSS Score Source: CVE-2020-25643

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.9

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

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

CVSS v3

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.6.0-1048-oem, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem-20.04

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2/25/2021

Vulnerability Publication Date: 5/19/2020

Reference Information

CVE: CVE-2020-10135, CVE-2020-14314, CVE-2020-15436, CVE-2020-15437, CVE-2020-24490, CVE-2020-25212, CVE-2020-25284, CVE-2020-25641, CVE-2020-25643, CVE-2020-25704, CVE-2020-27152, CVE-2020-27815, CVE-2020-28588, CVE-2020-28915, CVE-2020-29368, CVE-2020-29369, CVE-2020-29371, CVE-2020-29660, CVE-2020-29661, CVE-2020-35508

USN: 4752-1