147 lines
5.6 KiB
Text
147 lines
5.6 KiB
Text
-----BEGIN PGP SIGNED MESSAGE-----
|
|
Hash: SHA512
|
|
|
|
=============================================================================
|
|
FreeBSD-SA-20:21.usb_net Security Advisory
|
|
The FreeBSD Project
|
|
|
|
Topic: Potential memory corruption in USB network device drivers
|
|
|
|
Category: core
|
|
Module: kernel
|
|
Announced: 2020-08-05
|
|
Credits: Ilja van Sprundel, IOActive
|
|
Affects: All supported versions of FreeBSD.
|
|
Corrected: 2020-06-14 05:25:06 UTC (stable/12, 12.1-STABLE)
|
|
2020-08-05 17:11:18 UTC (releng/12.1, 12.1-RELEASE-p8)
|
|
2020-06-14 05:27:37 UTC (stable/11, 11.4-STABLE)
|
|
2020-08-05 17:11:18 UTC (releng/11.4, 11.4-RELEASE-p2)
|
|
2020-08-05 17:11:18 UTC (releng/11.3, 11.3-RELEASE-p12)
|
|
CVE Name: CVE-2020-7459
|
|
|
|
For general information regarding FreeBSD Security Advisories,
|
|
including descriptions of the fields above, security branches, and the
|
|
following sections, please visit <URL:https://security.FreeBSD.org/>.
|
|
|
|
I. Background
|
|
|
|
FreeBSD includes a number of USB Ethernet network interface device drivers,
|
|
including:
|
|
|
|
- smsc(4), supporting SMSC (now Microchip) devices
|
|
- muge(4), supporting Microchip devices
|
|
- cdceem(4), supporting USB Communication Device Class compatible devices
|
|
|
|
II. Problem Description
|
|
|
|
A missing length validation code common to these three drivers means that a
|
|
malicious USB device could write beyond the end of an allocated network
|
|
packet buffer.
|
|
|
|
III. Impact
|
|
|
|
An attacker with physical access to a USB port and the ability to bring a
|
|
network interface up may be able to use a specially crafted USB device to
|
|
gain kernel or user-space code execution.
|
|
|
|
IV. Workaround
|
|
|
|
No workaround is available. Systems with no active (i.e., UP) interface
|
|
supported by any of the smsc(4), muge(4), and cdceem(4) drivers are not
|
|
vulnerable.
|
|
|
|
Exploitation likely requires malicious USB hardware that emulates hardware
|
|
supported by one of these device drivers.
|
|
|
|
V. Solution
|
|
|
|
Upgrade your vulnerable system to a supported FreeBSD stable or
|
|
release / security branch (releng) dated after the correction date,
|
|
and reboot.
|
|
|
|
Perform one of the following:
|
|
|
|
1) To update your vulnerable system via a binary patch:
|
|
|
|
Systems running a RELEASE version of FreeBSD on the i386 or amd64
|
|
platforms can be updated via the freebsd-update(8) utility:
|
|
|
|
# freebsd-update fetch
|
|
# freebsd-update install
|
|
# shutdown -r +10min "Rebooting for a security update"
|
|
|
|
2) To update your vulnerable system via a source code patch:
|
|
|
|
The following patches have been verified to apply to the applicable
|
|
FreeBSD release branches.
|
|
|
|
a) Download the relevant patch from the location below, and verify the
|
|
detached PGP signature using your PGP utility.
|
|
|
|
[FreeBSD 12.x]
|
|
# fetch https://security.FreeBSD.org/patches/SA-20:21/usb_net.12.patch
|
|
# fetch https://security.FreeBSD.org/patches/SA-20:21/usb_net.12.patch.asc
|
|
# gpg --verify usb_net.12.patch.asc
|
|
|
|
[FreeBSD 11.x]
|
|
# fetch https://security.FreeBSD.org/patches/SA-20:21/usb_net.11.patch
|
|
# fetch https://security.FreeBSD.org/patches/SA-20:21/usb_net.11.patch.asc
|
|
# gpg --verify usb_net.11.patch.asc
|
|
|
|
b) Apply the patch. Execute the following commands as root:
|
|
|
|
# cd /usr/src
|
|
# patch < /path/to/patch
|
|
|
|
c) Recompile your kernel as described in
|
|
<URL:https://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the
|
|
system.
|
|
|
|
VI. Correction details
|
|
|
|
The following list contains the correction revision numbers for each
|
|
affected branch.
|
|
|
|
Branch/path Revision
|
|
- -------------------------------------------------------------------------
|
|
stable/12/ r362166
|
|
releng/12.1/ r363921
|
|
stable/11/ r362167
|
|
releng/11.4/ r363921
|
|
releng/11.3/ r363921
|
|
- -------------------------------------------------------------------------
|
|
|
|
To see which files were modified by a particular revision, run the
|
|
following command, replacing NNNNNN with the revision number, on a
|
|
machine with Subversion installed:
|
|
|
|
# svn diff -cNNNNNN --summarize svn://svn.freebsd.org/base
|
|
|
|
Or visit the following URL, replacing NNNNNN with the revision number:
|
|
|
|
<URL:https://svnweb.freebsd.org/base?view=revision&revision=NNNNNN>
|
|
|
|
VII. References
|
|
|
|
<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-7459>
|
|
|
|
The latest revision of this advisory is available at
|
|
<URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-20:21.usb_net.asc>
|
|
-----BEGIN PGP SIGNATURE-----
|
|
|
|
iQKTBAEBCgB9FiEE/A6HiuWv54gCjWNV05eS9J6n5cIFAl8q63dfFIAAAAAALgAo
|
|
aXNzdWVyLWZwckBub3RhdGlvbnMub3BlbnBncC5maWZ0aGhvcnNlbWFuLm5ldEZD
|
|
MEU4NzhBRTVBRkU3ODgwMjhENjM1NUQzOTc5MkY0OUVBN0U1QzIACgkQ05eS9J6n
|
|
5cIp7g//ZGKbxNKWsYEFXwNbBVbtkWMCQbj0V0TG2NReOsbYYhOolfkErZBpeTHt
|
|
iFJr5m3WY21a6ks/8up02HJyZ5oZwFFeMOMF/CKibZuym/8L8XgoU0uh/eHLiTvZ
|
|
qRf3p43xegcKgatFPggKA0yewNxMNETHI7BeO6+pkwYFQgb7f9GhM4JzC+DmaX6i
|
|
kyGcrnYoZzgKo2BGt65VRbvzucw/Su7wL4JutKhZlXDz7kxFv1gxB8Dqk9BBW9QM
|
|
EHejzhMCo6T0doYKLuZnz+SI2a/LOcTuNgR+5RnnxsVziLx+8csMNYy3YVw6JNXe
|
|
XC+8aJ7Un8BLKDoNJjoZ/J9IygJoaWgUa9+SH0pAtOeWhrfRUgd74ZZWfhiZkK5U
|
|
AXgY46c6Ce28TbEHTWgOAQgXRNB7iJgxVo6mTSnDt8t3YWh4t3g/rjHPKHagTNYC
|
|
aCd6gcJewb1Pw/8X/7H1FXRtUleHgMaxQ7ec8V5BwcXSexo4xZfq8qQTUbCuRmDg
|
|
4GaF8SondVb1TJxHwfq2wWvFhiwMWnRxwwjY6jkxiIjecc5vtrb2bwRq7nmKWciT
|
|
uV0jRj9ttP73ftE/zO94avXCbpCfHXMSpwaJMcs8PH+sHYXNhy0awuIped1ANXlh
|
|
E2jrNBW85gyKpnjfcAgECFid3Cu1V1xWo1BCTOWJXQjKi2Gaoa0=
|
|
=xbKP
|
|
-----END PGP SIGNATURE-----
|