High severity · published Mar 19, 2021
CVE-2021-27221
MikroTik RouterOS 6.47.9 allows remote authenticated ftp users to create or overwrite arbitrary .rsc files via the /export command
8.1
CVSS
4%
EPSS
No
On KEV
Description
MikroTik RouterOS 6.47.9 allows remote authenticated ftp users to create or overwrite arbitrary .rsc files via the /export command. NOTE: the vendor's position is that this is intended behavior because of how user policies work
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.0% · higher than 91% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RO
Routeros · Mikrotik
6.47.9 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27221
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27221
Exploit
https://onovy.medium.com/routeros-user-with-just-ftp-policy-can-write-to-filesystem-cve-2021-27221-e3e45d780dfe
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