CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
AI Score
Confidence
Low
EPSS
Percentile
28.0%
OpenPrinting reports:
Due to the service binding to *:631 ( INADDR_ANY ), multiple bugs
in cups-browsed can be exploited in sequence to introduce a
malicious printer to the system. This chain of exploits ultimately
enables an attacker to execute arbitrary commands remotely on the
target machine without authentication when a print job is started.
Posing a significant security risk over the network. Notably, this
vulnerability is particularly concerning as it can be exploited
from the public internet, potentially exposing a vast number of
systems to remote attacks if their CUPS services are enabled.
The vulnerability allows an attacker on the internet to create a
new printer device with arbitrary commands in the PPD file of the
printer. Attacks using mDNS on the local network can also replace an
existing printer. The commands are executed when a user attempts to
print on the malicious device. They run with the privileges of the
user “cups”.
It is recommended to disable the cups_browsed service until patches
become available. On FreeBSD this is the default. You can check the
status and disable the service with the following commands:
# service cups_browsed stop
# service cups_browsed disable
Attacks from the internet can be blocked by removing the “cups”
protocol from the BrowseRemoteProtocols and BrowseProtocols
directives in /usr/local/etc/cups/cups-browsed.conf. Attacks using
mDNS can be blocked by removing the “dnssd” protocol as well. Access
can be limited to specific IP addresses using BrowseAllow,
BrowseDeny, and BrowseOrder directives as documented in
cups-browsed.conf(5). Then restart the service with the following
command:
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
AI Score
Confidence
Low
EPSS
Percentile
28.0%