High severity · published Oct 29, 2019
CVE-2019-3977
RouterOS 6.45.6 Stable, RouterOS 6.44.5 Long-term, and below insufficiently validate where upgrade packages are download from when using the autoupgrade feature
7.5
CVSS
1.1%
EPSS
No
On KEV
Description
RouterOS 6.45.6 Stable, RouterOS 6.44.5 Long-term, and below insufficiently validate where upgrade packages are download from when using the autoupgrade feature. Therefore, a remote attacker can trick the router into "upgrading" to an older version of RouterOS and possibly reseting all the system's usernames and passwords.
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)1.1% · higher than 64% 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-2019-3977
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-3977
Third Party Advisory
https://www.tenable.com/security/research/tra-2019-46
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