#VU105997 Out-of-bounds write in smartdns - CVE-2023-31470

Vulnerability identifier: #VU105997

Vulnerability risk: High

CVSSv4.0: 6.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2023-31470

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
smartdns
Server applications / DNS servers

Vendor: Nick Peng

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing DNS responses within the _dns_encode_domain() function in dns.c. A remote attacker can send a specially crafted DNS response to the server, trigger an out-of-bounds write and execute arbitrary code on the target system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

smartdns: 18 - 41

---

External links
https://github.com/pymumu/smartdns/commit/56d0332bf91104cfc877635f6c82e9348587df04
https://github.com/pymumu/smartdns/issues/1378

---

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.