Vulnerability identifier: #VU56967

Vulnerability risk: Medium

CVSSv3.1: 6.4 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-3672

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
c-ares
Universal components / Libraries / Libraries used by multiple products

Vendor: c-ares.haxx.se

Description

The vulnerability allows a remote attacker to hijack domains.

The vulnerability exists due to insufficient validation of host names, returned by the DNS server. A remote attacker can pass specially crafted input to the application and perform domain hijacking.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

c-ares: 1.0.0 - 1.17.1

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External links
http://bugzilla.redhat.com/show_bug.cgi?id=1988342
http://c-ares.haxx.se/adv_20210810.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.