Synopsis
The remote NewStart CGSL host is affected by multiple vulnerabilities.
Description
The remote NewStart CGSL host, running version CORE 5.05 / MAIN 5.05, has dnsmasq packages installed that are affected by multiple vulnerabilities:
- A vulnerability was found in dnsmasq before version 2.81, where the memory leak allows remote attackers to cause a denial of service (memory consumption) via vectors involving DHCP response creation.
(CVE-2019-14834)
- A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in the forward.c:reply_query() if the reply destination address/port is used by the pending forwarded queries. However, it does not use the address/port to retrieve the exact forwarded query, substantially reducing the number of attempts an attacker on the network would have to perform to forge a reply and get it accepted by dnsmasq. This issue contrasts with RFC5452, which specifies a query's attributes that all must be used to match a reply. This flaw allows an attacker to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25685 or CVE-2020-25686, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity. (CVE-2020-25684)
- 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 Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.
Solution
Upgrade the vulnerable CGSL dnsmasq packages. Note that updated packages may not be available yet. Please contact ZTE for more information.
Plugin Details
File Name: newstart_cgsl_NS-SA-2021-0183_dnsmasq.nasl
Supported Sensors: Nessus
Risk Information
Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N
Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
CPE: p-cpe:/a:zte:cgsl_main:dnsmasq, p-cpe:/a:zte:cgsl_core:dnsmasq, cpe:/o:zte:cgsl_main:5, p-cpe:/a:zte:cgsl_core:dnsmasq-debuginfo, p-cpe:/a:zte:cgsl_main:dnsmasq-utils, p-cpe:/a:zte:cgsl_main:dnsmasq-debuginfo, cpe:/o:zte:cgsl_core:5, p-cpe:/a:zte:cgsl_core:dnsmasq-utils
Required KB Items: Host/local_checks_enabled, Host/ZTE-CGSL/release, Host/ZTE-CGSL/rpm-list, Host/cpu
Exploit Ease: No known exploits are available
Patch Publication Date: 9/24/2021
Vulnerability Publication Date: 1/7/2020