Ubuntu 16.04 ESM / 18.04 LTS : Linux kernel vulnerabilities (USN-5018-1)

high Nessus Plugin ID 151920

Synopsis

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

Description

The remote Ubuntu 16.04 ESM / 18.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-5018-1 advisory.

- The 802.11 standard that underpins Wi-Fi Protected Access (WPA, WPA2, and WPA3) and Wired Equivalent Privacy (WEP) doesn't require that received fragments be cleared from memory after (re)connecting to a network. Under the right circumstances, when another device sends fragmented frames encrypted using WEP, CCMP, or GCMP, this can be abused to inject arbitrary network packets and/or exfiltrate user data.
(CVE-2020-24586)

- The 802.11 standard that underpins Wi-Fi Protected Access (WPA, WPA2, and WPA3) and Wired Equivalent Privacy (WEP) doesn't require that all fragments of a frame are encrypted under the same key. An adversary can abuse this to decrypt selected fragments when another device sends fragmented frames and the WEP, CCMP, or GCMP encryption key is periodically renewed. (CVE-2020-24587)

- An issue was discovered in the kernel in NetBSD 7.1. An Access Point (AP) forwards EAPOL frames to other clients even though the sender has not yet successfully authenticated to the AP. This might be abused in projected Wi-Fi networks to launch denial-of-service attacks against connected clients and makes it easier to exploit other vulnerabilities in connected clients. (CVE-2020-26139)

- An issue was discovered in the Linux kernel 5.8.9. The WEP, WPA, WPA2, and WPA3 implementations reassemble fragments even though some of them were sent in plaintext. This vulnerability can be abused to inject packets and/or exfiltrate selected fragments when another device sends fragmented frames and the WEP, CCMP, or GCMP data-confidentiality protocol is used. (CVE-2020-26147)

- Bluetooth LE and BR/EDR secure pairing in Bluetooth Core Specification 2.1 through 5.2 may permit a nearby man-in-the-middle attacker to identify the Passkey used during pairing (in the Passkey authentication procedure) by reflection of the public key and the authentication evidence of the initiating device, potentially permitting this attacker to complete authenticated pairing with the responding device using the correct Passkey for the pairing session. The attack methodology determines the Passkey value one bit at a time. (CVE-2020-26558)

- Improper access control in BlueZ may allow an authenticated user to potentially enable information disclosure via adjacent access. (CVE-2021-0129)

- Use After Free vulnerability in nfc sockets in the Linux Kernel before 5.12.4 allows local attackers to elevate their privileges. In typical configurations, the issue can only be triggered by a privileged local user with the CAP_NET_RAW capability. (CVE-2021-23134)

- kernel/bpf/verifier.c in the Linux kernel through 5.12.1 performs undesirable speculative loads, leading to disclosure of stack content via side-channel attacks, aka CID-801c6058d14a. The specific concern is not protecting the BPF stack area against speculative loads. Also, the BPF stack can contain uninitialized data that might represent sensitive information previously operated on by the kernel. (CVE-2021-31829)

- net/bluetooth/hci_request.c in the Linux kernel through 5.12.2 has a race condition for removal of the HCI controller. (CVE-2021-32399)

- In the Linux kernel before 5.12.4, net/bluetooth/hci_event.c has a use-after-free when destroying an hci_chan, aka CID-5c4c8c954409. This leads to writing an arbitrary value. (CVE-2021-33034)

- kernel/bpf/verifier.c in the Linux kernel through 5.12.7 enforces incorrect limits for pointer arithmetic operations, aka CID-bb01a1bba579. This can be abused to perform out-of-bounds reads and writes in kernel memory, leading to local privilege escalation to root. In particular, there is a corner case where the off reg causes a masking direction change, which then results in an incorrect final aux->alu_limit.
(CVE-2021-33200)

- fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05. (CVE-2021-33909)

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-5018-1

Plugin Details

Severity: High

ID: 151920

File Name: ubuntu_USN-5018-1.nasl

Version: 1.9

Type: local

Agent: unix

Published: 7/21/2021

Updated: 1/9/2024

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

Risk Information

VPR

Risk Factor: Critical

Score: 9.5

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-2021-33909

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.5

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

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:16.04:-:esm, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1078-oracle, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1092-raspi2, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1097-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1106-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1109-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1109-snapdragon, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-1121-azure, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-151-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-151-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-4.15.0-151-lowlatency

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: 7/20/2021

Vulnerability Publication Date: 5/6/2021

Reference Information

CVE: CVE-2020-24586, CVE-2020-24587, CVE-2020-26139, CVE-2020-26147, CVE-2020-26558, CVE-2021-0129, CVE-2021-23134, CVE-2021-31829, CVE-2021-32399, CVE-2021-33034, CVE-2021-33200, CVE-2021-33909

IAVA: 2021-A-0350

USN: 5018-1