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.
Published 2021-01-20 16:15:14
Updated 2022-12-08 03:08:51
Source Red Hat, Inc.
View at NVD,   CVE.org

Products affected by CVE-2020-25685

Threat overview for CVE-2020-25685

Top countries where our scanners detected CVE-2020-25685
Top open port discovered on systems with this issue 53
IPs affected by CVE-2020-25685 1,117,145
Threat actors abusing to this issue? Yes
Find out if you* are affected by CVE-2020-25685!
*Directly or indirectly through your vendors, service providers and 3rd parties. Powered by attack surface intelligence from SecurityScorecard.

Exploit prediction scoring system (EPSS) score for CVE-2020-25685

0.24%
Probability of exploitation activity in the next 30 days EPSS Score History
~ 46 %
Percentile, the proportion of vulnerabilities that are scored at or less

CVSS scores for CVE-2020-25685

Base Score Base Severity CVSS Vector Exploitability Score Impact Score Score Source First Seen
4.3
MEDIUM AV:N/AC:M/Au:N/C:N/I:P/A:N
8.6
2.9
NIST
3.7
LOW CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
2.2
1.4
NIST

CWE ids for CVE-2020-25685

  • The product stores or transmits sensitive data using an encryption scheme that is theoretically sound, but is not strong enough for the level of protection required.
    Assigned by:
    • nvd@nist.gov (Primary)
    • secalert@redhat.com (Secondary)

References for CVE-2020-25685

Jump to
This web site uses cookies for managing your session, storing preferences, website analytics and additional purposes described in our privacy policy.
By using this web site you are agreeing to CVEdetails.com terms of use!