#VU53034 Integer overflow in Unbound - CVE-2019-25033

Vulnerability identifier: #VU53034

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2019-25033

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 in regional allocator. A remote attacker can pass specially crafted data to the server via the ALIGN_UP macro, 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
https://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/
https://lists.debian.org/debian-lts-announce/2021/05/msg00007.html
https://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.