CVE-2020-25686 is a flaw in dnsmasq, affecting versions prior to 2.83, including products from Arista, Debian, Fedora, and TheKelleys. This vulnerability allows an off-path attacker to significantly reduce the effort required to forge DNS replies and poison the dnsmasq cache due to the software not checking for existing pending requests for the same name. The attack has a low severity CVSS score of 3.7, with high attack complexity, and primarily impacts data integrity. While there is no known active exploitation or public exploit code (Metasploit, Nuclei, ExploitDB), the vulnerability has garnered significant community discussion and media coverage, indicating awareness and potential for future exploitation.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 2.83CPE matchmatch criteria | cpe:2.3:a:thekelleys:dnsmasq:*:*:*:*:*:*:*:* | ||
32CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* | ||
33CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | ||
10.0CPE matchmatch criteria | cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* | ||
>= 4.21, < 4.21.14mCPE matchmatch criteria | cpe:2.3:o:arista:eos:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.3 GitHub mentions.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
dnsmasq: multiple queries forwarded for the same name makes forging replies easier for an off-path attacker
Jan 19, 2021A 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.
Jan 12, 2021