MikroTik RouterOS DNS Cache Poisoning (CVE-2019-3978)

high Nessus Plugin ID 134714
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The remote network device is affected by a missing authentication vulnerability.


A vulnerability was discovered in MikroTik RouterOS. A missing authentication vulnerability exists in MikroTik RouterOS due to insufficient protections. An authenticated, remote attacker can exploit this, via the Winbox protocol by sending a crafted request, to trigger DNS queries. The queries are sent from the router to a server of the attacker's choice.
The requests are cached by the router, potentially resulting in cache poisoning.

Note that Nessus has sent a crafted request to the router to trigger a DNS request to the scanner in order to exploit this vulnerability.


Upgrade to MikroTik RouterOS 6.44.6 LTS, 6.45.7 or later.

See Also




Plugin Details

Severity: High

ID: 134714

File Name: mikrotik_cve-2019-3978.nbin

Version: 1.13

Type: remote

Family: Misc.

Published: 3/19/2020

Updated: 7/12/2021

Dependencies: mikrotik_winbox_detect.nasl

Risk Information

CVSS Score Source: CVE-2019-3978


Risk Factor: Medium

Score: 6.9


Risk Factor: Medium

Base Score: 5

Temporal Score: 4.3

Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N

Temporal Vector: E:H/RL:OF/RC:C


Risk Factor: High

Base Score: 7.5

Temporal Score: 7.2

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Temporal Vector: E:H/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:mikrotik:routeros

Required KB Items: Services/mikrotik_winbox

Exploit Available: true

Exploit Ease: Exploits are available

Exploited by Nessus: true

Patch Publication Date: 10/29/2019

Vulnerability Publication Date: 10/29/2019

Reference Information

CVE: CVE-2019-3978