5.3 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.011 Low
EPSS
Percentile
81.9%
Many machines (150K-180K) on the internet accept and route IP over IP by default.
IP-in-IP encapsulation is a tunneling protocol specified in RFC 2003 that allows for IP packets to be encapsulated inside another IP packets. This is very similar to IPSEC VPNs in tunnel mode, except in the case of IP-in-IP, the traffic is unencrypted. As specified, the protocol unwraps the inner IP packet and forwards this packet through IP routing tables, potentially providing unexpected access to network paths available to the vulnerable device. An IP-in-IP device is considered to be vulnerable if it accepts IP-in-IP packets from any source to any destination without explicit configuration between the specified source and destination IP addresses. This unexpected Data Processing Error (CWE-19) by a vulnerable device can be abused to perform reflective DDoS and in certain scenarios used to bypass network access control lists. Because the forwarded network packet may not be inspected or verified by vulnerable devices, there are possibly other unexpected behaviors that can be abused by an attacker on the target device or the target device’s network environment.
See full details here (“Description” copied here):
https://kb.cert.org/vuls/id/636397
An unauthenticated attacker can route network traffic through a vulnerable device, which may lead to reflective DDoS, information leak and bypass of network access controls.
5.3 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.011 Low
EPSS
Percentile
81.9%