High severity · published Oct 29, 2019
CVE-2019-3979
RouterOS versions 6.45.6 Stable, 6.44.5 Long-term, and below are vulnerable to a DNS unrelated data attack
7.5
CVSS
0.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 60% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RO
Routeros · Mikrotik
through 6.44.5; through 6.45.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-3979
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-3979
Third Party Advisory
https://www.tenable.com/security/research/tra-2019-46
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