Unauthenticated EAPOL-Key decryption in wpa_supplicant
Published: August 8, 2018
Identifiers:
- CVE-2018-14526
Latest version available from: https://w1.fi/security/2018-1/
Vulnerability
A vulnerability was found in how wpa_supplicant processes EAPOL-Key
frames. It is possible for an attacker to modify the frame in a way that
makes wpa_supplicant decrypt the Key Data field without requiring a
valid MIC value in the frame, i.e., without the frame being
authenticated. This has a potential issue in the case where WPA2/RSN
style of EAPOL-Key construction is used with TKIP negotiated as the
pairwise cipher. It should be noted that WPA2 is not supposed to be used
with TKIP as the pairwise cipher. Instead, CCMP is expected to be used
and with that pairwise cipher, this vulnerability is not applicable in
practice.
When TKIP is negotiated as the pairwise cipher, the EAPOL-Key Key Data
field is encrypted using RC4. This vulnerability allows unauthenticated
EAPOL-Key frames to be processed and due to the RC4 design, this makes
it possible for an attacker to modify the plaintext version of the Key
Data field with bitwise XOR operations without knowing the contents.
This can be used to cause a denial of service attack by modifying
GTK/IGTK on the station (without the attacker learning any of the keys)
which would prevent the station from accepting received group-addressed
frames. Furthermore, this might be abused by making wpa_supplicant act
as a decryption oracle to try to recover some of the Key Data payload
(GTK/IGTK) to get knowledge of the group encryption keys.
Full recovery of the group encryption keys requires multiple attempts
(128 connection attempts per octet) and each attempt results in
disconnection due to a failure to complete the 4-way handshake. These
failures can result in the AP/network getting disabled temporarily or
even permanently (requiring user action to re-enable) which may make it
impractical to perform the attack to recover the keys before the AP has
already changes the group keys. By default, wpa_supplicant is enforcing
at minimum a ten second wait time between each failed connection
attempt, i.e., over 20 minutes waiting to recover each octet while
hostapd AP implementation uses 10 minute default for GTK rekeying when
using TKIP. With such timing behavior, practical attack would need large
number of impacted stations to be trying to connect to the same AP to be
able to recover sufficient information from the GTK to be able to
determine the key before it gets changed.
Vulnerable versions/configurations
All wpa_supplicant versions.
Acknowledgments
Thanks to Mathy Vanhoef of the imec-DistriNet research group of KU
Leuven for discovering and reporting this issue.
Possible mitigation steps
- Remove TKIP as an allowed pairwise cipher in RSN/WPA2 networks. This
can be done also on the AP side.
- Merge the following commits to wpa_supplicant and rebuild:
WPA: Ignore unauthenticated encrypted EAPOL-Key data
This patch is available from https://w1.fi/security/2018-1/
- Update to wpa_supplicant v2.7 or newer, once available
Signed-off-by: John Crispin <john@phrozen.org>
The beacon_int is currently set explicitly for hostapd and when LEDE uses
iw to join and IBSS/mesh. But it was not done when wpa_supplicant was used
to join an encrypted IBSS or mesh.
This configuration is required when an AP interface is configured together
with an mesh interface. The beacon_int= line must therefore be re-added to
the wpa_supplicant config. The value is retrieved from the the global
variable.
Fixes: 1a16cb9c67 ("mac80211, hostapd: always explicitly set beacon interval")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name> [rebase]
(cherry picked from commit 772afef61d)
The wpa_supplicant code for IBSS allows to set the mcast rate. It is
recommended to increase this value from 1 or 6 Mbit/s to something higher
when using a mesh protocol on top which uses the multicast packet loss as
indicator for the link quality.
This setting was unfortunately not applied for mesh mode. But it would be
beneficial when wpa_supplicant would behave similar to IBSS mode and set
this argument during mesh join like authsae already does. At least it is
helpful for companies/projects which are currently switching to 802.11s
(without mesh_fwding and with mesh_ttl set to 1) as replacement for IBSS
because newer drivers seem to support 802.11s but not IBSS anymore.
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Tested-by: Simon Wunderlich <simon.wunderlich@openmesh.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name> [refresh]
(cherry picked from commit 43f66943d0)
RADIUS protocol could be used not only for authentication but for
accounting too. Accounting could be configured for any type of networks.
However there is no way to configure NAS Identifier for non-WPA
networks without this patch.
Signed-off-by: Yury Shvedov <yshvedov@wimarksystems.com>
[cleanup commit message]
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
(cherry picked from commit 37c1513b1f)
When sta is configured, hostapd receives 'stop' and 'update' command from
wpa_supplicant. In the update command, hostapd gets sta parameters with
which it configures ap.
Problem is, with the default wireless configuration:
mode:11g freq:2.4GHz channel:1
If sta is connected to 5GHz network, then ap does not work. Ideally with
340-reload_freq_change.patch hostapd should reload the frequency changes
and start ap in 5GHz, but ap becomes invisible in the network.
This issue can be reproduced with following /etc/config/wireless:
config wifi-device radio0
option type mac80211
option channel 1
option hwmode 11g
option path 'virtual/uccp420/uccwlan'
option htmode 'none'
config wifi-iface 'ap'
option device 'radio0'
option encryption 'none'
option mode 'ap'
option network 'ap'
option ssid 'MyTestNet'
option encryption none
config wifi-iface 'sta'
option device radio0
option network sta
option mode sta
option ssid TestNet-5G
option encryption psk2
option key 12345
This change updates current_mode structure based on configured hw_mode
received from wpa_supplicant. Also prepare rates table after frequency
selection.
Signed-off-by: Abhilash Tuse <Abhilash.Tuse@imgtec.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name> [cleanup, patch refresh]
(cherry picked from commit 41feba8c4a)
wpa_disable_eapol_key_retries can't prevent attacks against the Wireless
Network Management (WNM) Sleep Mode handshake. Currently, hostapd
processes WNM Sleep Mode requests from clients regardless of the setting
wnm_sleep_mode. Backport Jouni Malinen's upstream patch 114f2830 in
order to ignore such requests by clients when wnm_sleep_mode is disabled
(which is the default).
Signed-off-by: Timo Sigurdsson <public_timo.s@silentcreek.de>
[rewrite commit subject (<= 50 characters), bump PKG_RELEASE]
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
(cherry picked from commit bd45e15d0a
fixed PKG_RELEASE and renumbered patch)
Conflicts:
package/network/services/hostapd/Makefile
wpa_disable_eapol_key_retries can't prevent attacks against the
Tunneled Direct-Link Setup (TDLS) handshake. Jouni Malinen suggested
that the existing hostapd option tdls_prohibit can be used to further
complicate this possibility at the AP side. tdls_prohibit=1 makes
hostapd advertise that use of TDLS is not allowed in the BSS.
Note: If an attacker manages to lure both TDLS peers into a fake
AP, hiding the tdls_prohibit advertisement from them, it might be
possible to bypass this protection.
Make this option configurable via UCI, but disabled by default.
Signed-off-by: Timo Sigurdsson <public_timo.s@silentcreek.de>
(cherry picked from commit 6515887ed9)
Commit b6c3931ad6 introduced an AP-side
workaround for key reinstallation attacks. This option can be used to
mitigate KRACK on the station side, in case those stations cannot be
updated. Since many devices are out there will not receive an update
anytime soon (if at all), it makes sense to include this workaround.
Unfortunately this can cause interoperability issues and reduced
robustness of key negotiation, so disable the workaround by default, and
add an option to allow the user to enable it if he deems necessary.
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
(cherry picked from commit c5f97c9372)
While these changes are not included in the advisory, upstream
encourages users to merge them.
See http://lists.infradead.org/pipermail/hostap/2017-October/037989.html
Added 013-Add-hostapd-options-wpa_group_update_count-and-wpa_p.patch so
that 016-Optional-AP-side-workaround-for-key-reinstallation-a.patch
applies without having to rework it.
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
Fix multiple syntax errors in shelscripts (of packages only)
These errors were causing many conditions to not working properly
Signed-off-by: Lorenzo Santina <lorenzo.santina@edu.unito.it>
[increase PKG_RELEASE, drop command substitution from directip.sh]
Signed-off-by: Mathias Kresin <dev@kresin.em>
ifname variable were not assigned due to syntax error
causing the hostapd config file to have an empty iapp_interface= option
Signed-off-by: Lorenzo Santina <lorenzo.santina.dev@gmail.com>
One of the latest mac80211 updates added sanity checks, requiring the
beacon intervals of all VIFs of the same radio to match. This often broke
AP+11s setups, as these modes use different default intervals, at least in
some configurations (observed on ath9k).
Instead of relying on driver or hostapd defaults, change the scripts to
always explicitly set the beacon interval, defaulting to 100. This also
applies the beacon interval to 11s interfaces, which had been forgotten
before. VIF-specific beacon_int setting is removed from hostapd.sh.
Fixes FS#619.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Setting legacy_rates to 0 disables 802.11b data rates.
Setting legacy_rates to 1 enables 802.11b data rates. (Default)
The basic_rate option and supported_rates option are filtered based on this.
The rationale for the change, stronger now than in 2014, can be found in:
https://mentor.ieee.org/802.11/dcn/14/11-14-0099-00-000m-renewing-2-4ghz-band.pptx
The balance of equities between compatibility with b clients and the
detriment to the 2.4 GHz ecosystem as a whole strongly favors disabling b
rates by default.
Signed-off-by: Nick Lowe <nick.lowe@gmail.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name> [cleanup, defaults change]
- Fix eap test to work with standalone hostapd builds
- Fix 11n test to check the correct define
- Add 11ac, 11r and 11w tests
Signed-off-by: Jo-Philipp Wich <jo@mein.io>
This will allow starting hostapd with the new -s parameter and finally
read all (error) messages from the syslog.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
It wasn't possible to read hostapd wpa_printf messages unless running
hostapd manually. It was because hostapd was printing them using vprintf
and not directly to the syslog.
We were trying to workaround this problem by redirecting STDIN_FILENO
and STDOUT_FILENO but it was working only for the initialization phase.
As soon as hostapd did os_daemonize our solution stopped working.
Please note despite the subject this change doesn't affect debug level
messages only but just everything printed by hostapd with wpa_printf
including MSG_ERROR-s. This makes it even more important as reading
error messages can be quite useful for debugging.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
ap_setup_locked is named wps_ap_setup_locked in uci for consistency with other
wps related uci options.
Signed-off-by: Steven Honson <steven@honson.id.au>
The hostapd_append_wpa_key_mgmt() procedure uses the possibly uninitialized
$ieee80211r and $ieee80211w variables in a numerical comparisation, leading
to stray "netifd: radio0 (0000): sh: out of range" errors in logread when
WPA-PSK security is enabled.
Ensure that those variables are substituted with a default value in order to
avoid emitting this (harmless) shell error.
Signed-off-by: Jo-Philipp Wich <jo@mein.io>
wpa_supplicant allows only SAE as the key management
type for mesh mode. The recent key_mgmt rework unconditionally
added WPA-PSK - this breaks interface bringup and wpa_s
throws this error message:
Line 10: key_mgmt for mesh network should be open or SAE
Line 10: failed to parse network block.
Failed to read or parse configuration '/var/run/wpa_supplicant-wlan0.conf
Fix this by making sure that only SAE is used for mesh.
Signed-off-by: Sujith Manoharan <m.sujith@gmail.com>
Enable support for stronger SHA256-based algorithms in hostapd and
wpa_supplicant when using WPA-EAP or WPA-PSK with 802.11w enabled.
We cannot unconditionally enable it, as it requires hostapd to be
compiled with 802.11w support, which is disabled in the -mini variants.
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
Tested-by: Sebastian Kemper <sebastian_ml@gmx.net>
Now that wpa_key_mgmt handling for hostapd and wpa_supplicant are
consistent, we can move parts of it to a dedicated function.
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
Tested-by: Sebastian Kemper <sebastian_ml@gmx.net>
Rework wpa_key_mgmt handling for wpa_supplicant to be consistent with
how it is done for hostapd.
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
Tested-by: Sebastian Kemper <sebastian_ml@gmx.net>
Update to latest upstream HEAD:
- Refreshed all
- Delete patches and parts which made it upstream
Compile tested Full & Mini configs
Run-tested Mini config
Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name> [another update, remove broken patch]
The build system only accepts Package/<name>/description and since the
typoed version virtually has the same content as the TITLE field, remove
them altogether
Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
Ensure that selecting the wpa-supplicant-mesh package actually packages the
wpa_supplicant binary with SAE support and add missing dependency on OpenSSL.
Signed-off-by: Alexis Green <alexis@cessp.it>
[Jo-Philipp Wich: slightly reword commit message for clarity]
Signed-off-by: Jo-Philipp Wich <jo@mein.io>
This more of a demo for the previous commit that comes with
this one, where I added support for copying source from 'src' to
the build dir(s).
Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>
* Change git packages to xz
* Update mirror checksums in packages where they are used
* Change a few source tarballs to xz if available upstream
* Remove unused lines in packages we're touching, requested by jow- and blogic
* We're relying more on xz-utils so add official mirror as primary source, master site as secondary.
* Add SHA256 checksums to multiple git tarball packages
Signed-off-by: Daniel Engberg <daniel.engberg.lists@pyret.net>
RADIUS accounting can be used even when RADIUS authentication is not
used. Move the accounting configuration outside of the EAP-exclusive
sections.
Signed-off-by: Petko Bordjukov <bordjukov@gmail.com>
