cve/2020/CVE-2020-25685.md

### [CVE-2020-25685](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-25685)
![](https://img.shields.io/static/v1?label=Product&message=dnsmasq&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-326&color=brighgreen)

### Description

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.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/AZ-X/pique
- https://github.com/CVEDB/PoC-List
- https://github.com/CVEDB/awesome-cve-repo
- https://github.com/CVEDB/top
- https://github.com/DNTYO/F5_Vulnerability
- https://github.com/EdgeSecurityTeam/Vulnerability
- https://github.com/GhostTroops/TOP
- https://github.com/JERRY123S/all-poc
- https://github.com/Live-Hack-CVE/CVE-2020-25685
- https://github.com/SexyBeast233/SecBooks
- https://github.com/criminalip/CIP-NSE-Script
- https://github.com/cyberanand1337x/bug-bounty-2022
- https://github.com/hktalent/TOP
- https://github.com/jbmihoub/all-poc
- https://github.com/kaosagnt/ansible-everyday
- https://github.com/klcheung99/CSCM28CW2
- https://github.com/knqyf263/dnspooq
- https://github.com/mboukhalfa/multironic
- https://github.com/tzwlhack/Vulnerability
- https://github.com/weeka10/-hktalent-TOP