In response to the heartbleed (CVE-2014-0160) vulnerability, on April
9th 2014 we updated the under-development CeroWrt release to include
the fixed version of openssl. The fix is in CeroWrt 3.10.36-3 and
We have no means of fixing the "stable" (3.7.5) release of CeroWrt,
nor any of the innumerable development releases since then.
Please do a clean, fresh upgrade to CeroWrt 3.10.36-6 or later. 
Images are available in: http://snapon.lab.bufferbloat.net/~cero2/cerowrt/wndr/
Reflashing instructions are here:
In the base image, the administration gui of recent CeroWrt versions
depended on openssl (however it is protected by firewall rules to only
be accessible from within your own network), and several optional packages
did also - stunnel - used for "secure" tunneling, and openvpn in particular.
Heartbleed is one of the most serious bugs that has ever hit the
internet, and in addition to web services, critical network daemons
such as those that manage network printing, logging, monitoring, voip,
chat, tunnels, vpns and email, all can potentially be exploited.
We strongly advise resyncing your source trees with us and distributing
new firmware images containing the updated libraries. All
network facing TLS-using daemons are potentially a risk, as are
any TLS using services exposed behind the firewall.
Once your system is secured again, you should re-issue certs and passwords,
as per: https://www.eff.org/deeplinks/2014/04/bleeding-hearts-club-heartbleed-recovery-system-administrators
and check for unverified commits.
Packages maintained in the openwrt core repositories that can be
affected when compiled for openssl2 may include: libevent2,
ustream-ssl, hostapd, openvpn, authsae, luci-ssl, and uhttpd.
Optional network daemons in other repositories such as radsecproxy,
vsftpd, squid, mini_httpd, pure-ftpd, cups, ndyndns, elinks,
libtorrent, monit, nagios, syslog-ng3, boxbackup, rsyncrypto, curl,
cyrus-sasl, openldap, icecast, fetchmail, dovecot, transmission,
stunnel, httptunnel, apache, lighttpd, znc, net-snmp, bitlbee,
asterisk, postfix and openvpn all use TLS level security, are
often linked against openssl, and are thus potentially vulnerable.
Please see the relevant website for each of the products above
for news on their vulnerabilities. Much of the furor over heartbleed
has focused on websites, where notably smtp and imaps and im traffic
has also been shown vulnerable.
Other infrastructure, router and CPE distributions are also affected.
Two examples among many:
Network facing Applications built on top of php4, php5, python, luasec, erlang, ruby
are also potentially affected.
Packages maintained in the ceropackages repository that were potentially
vulnerable are xorp, python-lafs, ccnx, and resiprocate.
Please take this seriously and check your firmware and your products for
usage of the vulnerable openssl versions.
We note also that multiple other serious vulnerabilities have been
fixed in other CeroWrt and OpenWrt packages and in the Linux kernel over
the past years; you should consider fixing those vulnerabilities in
your downstream products and routers while you are at it.
We have long been supportive of adding new features for openwrt to
make it more easily updated in the field, the work could use more
eyeballs and developers, and we need to find resources and funding for
a code audit in the coming months.
 Regrettably in the present development branch (3.10.36-4) we are
trying to isolate a wifi bug that crops up after much traffic, we will
announce a fix for that when it arrives. See Bug #442 .
 The base as-provided-by OpenWrt base binary installations are not
vulnerable to HeartBleed, as neither the builtin SSH server nor the
optional LuCI SSL support rely on OpenSSL for cryptographic TLS
support. Their Attitude Adjustment release used cyassl as a base,
and the underway Barrier Breaker development series uses PolarSSL
for as many packages as support exists and the GPLv2 license allows.
In other words the OpenSSL library is not installed within the stock
base images available on their download servers, however they too
contain many optional packages that do depend on openssl to function,
and many downstream products may have chosen openssl over those
Check your trees! And if you are having a bad week, perhaps this
will help: http://www.taht.net/~mtaht/uncle_bills_helicopter.html
Stay calm and keep on patching!
Jim Gettys will be giving a talk at MIT about insecurity
in home devices and what can be done about it.
For more details, see:
Dave Taht had a chance to summarize the last 9 or so months of development in the Linux TCP and AQM/Packet Scheduling stack at Cambridge after the IETF meeting earlier this month.
The slides are now up at:
Our mail server is suffering from a failed hard disk in the raid array. Replacing now. Hopefully it will come back up.
In the long run, we need to move this box to a virtual somewhere.
CeroWrt News - January 2014¶
The newest build of CeroWrt - 3.10.24-8 - is working quite well for us. There's a Release Note page that gives the current status. Note that, although it has been very stable, this is still an experimental release. It's available at http://snapon.lab.bufferbloat.net/~cero2/cerowrt/wndr/3.10.24-8/
The CeroWrt development team has been working to nail down a no-brainer set of instructions for eliminating bufferbloat - the lag/latency that kills voice & video chat, gaming, and overall network responsiveness. The hard part is that optimal configuration of the Smart Queue Management (SQM) link is difficult - there are tons of options an ISP can set. Although CeroWrt can adapt to any of them, it's difficult to find out the exact characteristics of the link you have. Check out the latest version of our instructions at http://www.bufferbloat.net/projects/cerowrt/wiki/Setting_up_AQM_for_CeroWrt_310
Although the CeroWrt site (http://www.bufferbloat.net/projects/cerowrt/) has been quiet, that doesn't mean that we haven't been working.
The CeroWrt-Devel mailing list (https://lists.bufferbloat.net/listinfo/cerowrt-devel) has been bubbling with lots of energy all summer and fall, and we're getting close to a new release that we can recommend to everyone. Here's what's we've been working on:
- Significant refinement to the CoDel code, to further knock down bufferbloat
- Update to Linux 3.10 kernel that incorporates much of our earlier work on bufferbloat
- All the good effort from the OpenWrt Barrier Breaker development firmware
- And too many other improvements to mention here
You can check out any number of Bufferbloat videos at http://www.bufferbloat.net/projects/cerowrt/wiki/Bloat-videos to learn more about the problem and our solutions.
If you just want good router firmware, purchase a Netgear WNDR3800 and burn the current 3.7.5-2 firmware. You can also follow our activity on the CeroWrt-devel list to see what's happening and learn when experimental builds or solid new releases are available.
What can I say? 3.7.5-2 has been deployed and thoroughly tested at multiple sites, and under high load, and on places like comcast's cable network, and it just. keeps. working.
In this release:
Vastly improved ipv6 naming and interopability, 3 new forms of codel and fq_codel, much better QoS...
And all the chocolately goodness from OpenWrt Barrier Breaker.
More news to come. Thank you all for your support and donations! We couldn't have done it without you.
[[Best Practices for Benchmarking CoDel and FQ CoDel]] contains lots of useful information for people experimenting with the current (Linux 3.6) CoDel and fq_codel implementations. If you don't take care, you may get bad data.
The Internet Society has issued another in its series on Bandwidth Management, in its Technology Roundtable Series. The executive summary highlights the problems that bufferbloat is causing in today's Internet. The full report is available.
*With apologies to Stuart Cheshire...
I've been working fixing bufferbloat now for a really long time, and of late it's been really difficult to keep the lights on and the servers fed. Last month I'd hit bottom, this month is worse. I put up a donations page, and got a totally wonderful level of response - enough to make rent! Then I tripped over an obscure portion of the Amazon EULA, and ended up refunding everyone's money and cancelling your subscriptions.
So, I've put up a new subscribe/donations page for the cerowrt portion of the project, using paypal at:
I won't jimmy wales you'all on further solicitations like this. (I know, that's what I said last month)
But a little more help in getting over this hump would be very nice to have.
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