EulerOS 2.0 SP3 : dnsmasq (EulerOS-SA-2021-1775)

high Nessus Plugin ID 149190

Synopsis

The remote EulerOS host is missing multiple security updates.

Description

According to the versions of the dnsmasq packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

- A vulnerability was found in the implementation of DNSSEC in Dnsmasq up to and including 2.78. Wildcard synthesized NSEC records could be improperly interpreted to prove the non-existence of hostnames that actually exist.(CVE-2017-15107)

- A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in forward.c:reply_query(), which is the forwarded query that matches the reply, by only using a weak hash of the query name. Due to the weak hash (CRC32 when dnsmasq is compiled without DNSSEC, SHA-1 when it is) this flaw allows an off-path attacker to find several different domains all having the same hash, substantially reducing the number of attempts they would have to perform to forge a reply and get it accepted by dnsmasq. This is in contrast with RFC5452, which specifies that the query name is one of the attributes of a query that must be used to match a reply. This flaw could be abused to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25684 the attack complexity of a successful attack is reduced.
The highest threat from this vulnerability is to data integrity.(CVE-2020-25685)

- A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the same name. This flaw allows an off-path attacker on the network to substantially reduce the number of attempts that it would have to perform to forge a reply and have it accepted by dnsmasq. This issue is mentioned in the 'Birthday Attacks' section of RFC5452. If chained with CVE-2020-25684, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.(CVE-2020-25686)

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 dnsmasq packages.

See Also

http://www.nessus.org/u?4be2b5e9

Plugin Details

Severity: High

ID: 149190

File Name: EulerOS_SA-2021-1775.nasl

Version: 1.2

Type: local

Published: 4/30/2021

Updated: 5/4/2021

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

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:H/A:N

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

Vulnerability Information

CPE: p-cpe:/a:huawei:euleros:dnsmasq, p-cpe:/a:huawei:euleros:dnsmasq-utils, cpe:/o:huawei:euleros:2.0

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

Excluded KB Items: Host/EulerOS/uvp_version

Exploit Ease: No known exploits are available

Patch Publication Date: 4/30/2021

Reference Information

CVE: CVE-2017-15107, CVE-2020-25685, CVE-2020-25686