CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:N/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
Percentile
85.0%
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.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 18.04 | noarch | dnsmasq | < 2.79-1ubuntu0.2 | UNKNOWN |
ubuntu | 20.04 | noarch | dnsmasq | < 2.80-1.1ubuntu1.2 | UNKNOWN |
ubuntu | 20.10 | noarch | dnsmasq | < 2.82-1ubuntu1.1 | UNKNOWN |
ubuntu | 21.04 | noarch | dnsmasq | < 2.82-1ubuntu2 | UNKNOWN |
ubuntu | 21.10 | noarch | dnsmasq | < 2.82-1ubuntu2 | UNKNOWN |
ubuntu | 22.04 | noarch | dnsmasq | < 2.82-1ubuntu2 | UNKNOWN |
ubuntu | 22.10 | noarch | dnsmasq | < 2.82-1ubuntu2 | UNKNOWN |
ubuntu | 23.04 | noarch | dnsmasq | < 2.82-1ubuntu2 | UNKNOWN |
ubuntu | 23.10 | noarch | dnsmasq | < 2.82-1ubuntu2 | UNKNOWN |
ubuntu | 24.04 | noarch | dnsmasq | < 2.82-1ubuntu2 | UNKNOWN |
lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2021q1/014599.html
launchpad.net/bugs/cve/CVE-2020-25686
nvd.nist.gov/vuln/detail/CVE-2020-25686
security-tracker.debian.org/tracker/CVE-2020-25686
ubuntu.com/security/notices/USN-4698-1
www.cve.org/CVERecord?id=CVE-2020-25686
www.jsof-tech.com/disclosures/dnspooq/
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:N/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
Percentile
85.0%