Ubuntu 21.04 : Linux kernel vulnerabilities (USN-4950-1)

high Nessus Plugin ID 149406

Synopsis

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

Description

The remote Ubuntu 21.04 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4950-1 advisory.

Ryota Shiga discovered that the eBPF implementation in the Linux kernel did not properly verify that a BPF program only reserved as much memory for a ring buffer as was allocated. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-3489)

Manfred Paul discovered that the eBPF implementation in the Linux kernel did not properly track bounds on bitwise operations. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-3490)

Billy Jheng Bing-Jhong discovered that the io_uring implementation of the Linux kernel did not properly enforce the MAX_RW_COUNT limit in some situations. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-3491)

Norbert Slusarek discovered that the CAN ISOTP protocol implementation in the Linux kernel contained a race condition. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. Please note that to address this issue, SF_BROADCAST support was removed temporarily from the CAN ISOTP implementation in Ubuntu 21.04 kernels. (LP: #1927409)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

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 packages.

See Also

https://ubuntu.com/security/notices/USN-4950-1

Plugin Details

Severity: High

ID: 149406

File Name: ubuntu_USN-4950-1.nasl

Version: 1.8

Type: local

Agent: unix

Published: 5/12/2021

Updated: 8/27/2024

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

Risk Information

VPR

Risk Factor: Critical

Score: 9.6

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.3

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

CVSS Score Source: CVE-2021-3491

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 8.4

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

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

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-hwe-20.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1008-raspi, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-hwe-20.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1007-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-gke, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1005-azure, p-cpe:/a:canonical:ubuntu_linux:linux-image-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-oracle, p-cpe:/a:canonical:ubuntu_linux:linux-image-azure, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1007-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-hwe-20.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-17-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-17-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-17-generic-64k, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1006-oracle, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1007-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-hwe-20.04-edge, cpe:/o:canonical:ubuntu_linux:21.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-1008-raspi-nolpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.11.0-17-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi-nolpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-64k, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-64k-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-64k-hwe-20.04-edge

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/11/2021

Vulnerability Publication Date: 5/11/2021

Exploitable With

Core Impact

Metasploit (Linux eBPF ALU32 32-bit Invalid Bounds Tracking LPE)

Reference Information

CVE: CVE-2021-3489, CVE-2021-3490, CVE-2021-3491

USN: 4950-1