CVE-2019-3979 RouterOS versions 6.45.6 Stable, 6.44.5 Long-term, and below are vulnerable to a DNS unrelated data attack.

What is CVE-2019-3979?

CVE-2019-3979 is a high-severity vulnerability in Mikrotik Routeros, published on 28 Oct 2019.

Official description

RouterOS versions 6.45.6 Stable, 6.44.5 Long-term, and below are vulnerable to a DNS unrelated data attack. The router adds all A records to its DNS cache even when the records are unrelated to the domain that was queried. Therefore, a remote attacker controlled DNS server can poison the router's DNS cache via malicious responses with additional and untrue records.

Weakness: CWE-345

Which versions are affected by CVE-2019-3979?

It affects 1 product.

Products include Mikrotik Routeros.

How do I fix CVE-2019-3979?

No fix has been published for CVE-2019-3979 yet. Limit exposure of the affected software until one is available.

Is CVE-2019-3979 being exploited?

There is no known exploitation of CVE-2019-3979 in the wild and no public exploit code.

Other vulnerabilities in Mikrotik Routeros

• CVE-2018-7445 MikroTik RouterOS Stack-Based Buffer Overflow Exploited Critical 9.8
• CVE-2026-86060 MikroTik RouterOS Improper Neutralization of Argument Delimiters in a Command Exploited Critical 9.2
• CVE-2018-14847 MikroTik Router OS Directory Traversal Exploited Critical 9.1
• CVE-2026-67277 MikroTik RouterOS Missing Authentication for Critical Function Exploited High 8.8
• CVE-2026-67279 Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Exploited Medium 6.9

All Mikrotik Routeros vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-hxg2-8cqf-77j7.