8.6 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
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
0.006 Low
EPSS
Percentile
78.9%
An issue was discovered in the IPv6 protocol specification, related to ICMP
Packet Too Big (PTB) messages. (The scope of this CVE is all affected IPv6
implementations from all vendors.) The security implications of IP
fragmentation have been discussed at length in [RFC6274] and [RFC7739]. An
attacker can leverage the generation of IPv6 atomic fragments to trigger
the use of fragmentation in an arbitrary IPv6 flow (in scenarios in which
actual fragmentation of packets is not needed) and can subsequently perform
any type of fragmentation-based attack against legacy IPv6 nodes that do
not implement [RFC6946]. That is, employing fragmentation where not
actually needed allows for fragmentation-based attack vectors to be
employed, unnecessarily. We note that, unfortunately, even nodes that
already implement [RFC6946] can be subject to DoS attacks as a result of
the generation of IPv6 atomic fragments. Let us assume that Host A is
communicating with Host B and that, as a result of the widespread dropping
of IPv6 packets that contain extension headers (including fragmentation)
[RFC7872], some intermediate node filters fragments between Host B and Host
A. If an attacker sends a forged ICMPv6 PTB error message to Host B,
reporting an MTU smaller than 1280, this will trigger the generation of
IPv6 atomic fragments from that moment on (as required by [RFC2460]). When
Host B starts sending IPv6 atomic fragments (in response to the received
ICMPv6 PTB error message), these packets will be dropped, since we
previously noted that IPv6 packets with extension headers were being
dropped between Host B and Host A. Thus, this situation will result in a
DoS scenario. Another possible scenario is that in which two BGP peers are
employing IPv6 transport and they implement Access Control Lists (ACLs) to
drop IPv6 fragments (to avoid control-plane attacks). If the aforementioned
BGP peers drop IPv6 fragments but still honor received ICMPv6 PTB error
messages, an attacker could easily attack the corresponding peering session
by simply sending an ICMPv6 PTB message with a reported MTU smaller than
1280 bytes. Once the attack packet has been sent, the aforementioned
routers will themselves be the ones dropping their own traffic.
Author | Note |
---|---|
jdstrand | android kernels (flo, goldfish, grouper, maguro, mako and manta) are not supported on the Ubuntu Touch 14.10 and earlier preview kernels linux-lts-saucy no longer receives official support linux-lts-quantal no longer receives official support |
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-10142
git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?id=9d289715eb5c252ae15bd547cb252ca547a3c4f2
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9d289715eb5c252ae15bd547cb252ca547a3c4f2
launchpad.net/bugs/cve/CVE-2016-10142
nvd.nist.gov/vuln/detail/CVE-2016-10142
security-tracker.debian.org/tracker/CVE-2016-10142
tools.ietf.org/html/draft-ietf-6man-deprecate-atomfrag-generation-08
tools.ietf.org/html/rfc8021
8.6 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
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
0.006 Low
EPSS
Percentile
78.9%