Vulnerability identifier: #VU53033

Vulnerability risk: High

CVSSv3.1: 8.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-25034

CWE-ID: CWE-190

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Unbound
Server applications / DNS servers

Vendor: NLnet Labs

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to integer overflow within the sldns_str2wire_dname_buf_origin() function. A remote attacker can pass specially crafted data to the server, trigger integer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Unbound: 1.0.0 - 1.9.4

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External links
http://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/
http://lists.debian.org/debian-lts-announce/2021/05/msg00007.html
http://security.netapp.com/advisory/ntap-20210507-0007/

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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.