EulerOS Virtualization 3.0.2.2 : unbound (EulerOS-SA-2021-2172)

high Nessus Plugin ID 151378
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote EulerOS Virtualization host is missing multiple security updates.

Description

According to the versions of the unbound package installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

- NLnet Labs Unbound, up to and including version 1.12.0, and NLnet Labs NSD, up to and including version 4.3.3, contain a local vulnerability that would allow for a local symlink attack. When writing the PID file, Unbound and NSD create the file if it is not there, or open an existing file for writing. In case the file was already present, they would follow symlinks if the file happened to be a symlink instead of a regular file. An additional chown of the file would then take place after it was written, making the user Unbound/NSD is supposed to run as the new owner of the file. If an attacker has local access to the user Unbound/NSD runs as, she could create a symlink in place of the PID file pointing to a file that she would like to erase. If then Unbound/NSD is killed and the PID file is not cleared, upon restarting with root privileges, Unbound/NSD will rewrite any file pointed at by the symlink. This is a local vulnerability that could create a Denial of Service of the system Unbound/NSD is running on. It requires an attacker having access to the limited permission user Unbound/NSD runs as and point through the symlink to a critical file on the system.(CVE-2020-28935)

- Unbound before 1.10.1 has Insufficient Control of Network Message Volume, aka an 'NXNSAttack' issue. This is triggered by random subdomains in the NSDNAME in NS records.(CVE-2020-12662)

- Unbound before 1.10.1 has an infinite loop via malformed DNS answers received from upstream servers.(CVE-2020-12663)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected unbound packages.

See Also

http://www.nessus.org/u?7bb71aaf

Plugin Details

Severity: High

ID: 151378

File Name: EulerOS_SA-2021-2172.nasl

Version: 1.2

Type: local

Published: 7/6/2021

Updated: 7/8/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 5.1

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

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

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: p-cpe:/a:huawei:euleros:unbound-libs, cpe:/o:huawei:euleros:uvp:3.0.2.2

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/EulerOS/release, Host/EulerOS/rpm-list, Host/EulerOS/uvp_version

Exploit Ease: No known exploits are available

Patch Publication Date: 7/6/2021

Reference Information

CVE: CVE-2020-12662, CVE-2020-12663, CVE-2020-28935