From time to time a customer writes in and asks about certain requests that have been blocked by the CloudFlare WAF. Recently, a customer couldn’t understand why it appeared that some simple GET requests for their homepage were listed as blocked in WAF analytics.
A sample request looked liked this:
GET / HTTP/1.1
Host: www.example.com
Connection: keep-alive
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (compatible; MSIE 11.0; Windows NT 6.1; Win64; x64; Trident/5.0)'+(select*from(select(sleep(20)))a)+'
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8,fr;q=0.6
As I said, a simple request for the homepage of the web site, which at first glance doesn’t look suspicious at all. Unless your take a look at the User-Agent header (its value is the string that identifies the browser being used):
Mozilla/5.0 (compatible; MSIE 11.0; Windows NT 6.1; Win64; x64; Trident/5.0)'+(select*from(select(sleep(20)))a)+
The start looks reasonable (it’s apparently Microsoft Internet Explorer 11) but the agent strings ends with '+(select*from(select(sleep(20)))a)+. The attacker is attempting a SQL injection inside the User-Agent value.
It’s common to see SQL injection in URIs and form parameters, but here the attacker has hidden the SQL query select * from (select(sleep(20))) inside the User-Agent Continue reading
This post is the last one I’m planning in this series on Label Switched Multicast (LSM). The questions & answers below are meant to expand on topics from the previous posts or address topics that weren’t mentioned in the previous posts at all.
If you’re not familiar with LSM yet then this Q&A likely won’t make much sense to you and I recommend you go back and read through the previous posts.
Please post a comment if one of the answers isn’t clear or you have additional questions!
If you have a (*,G) or an (S,G), the following commands will show you which MDT is being used through the MPLS core. I find the easiest place in the network to check the mapping between a (*,G) or (S,G) and an MDT is on the Ingress PE. Two tables hold the mapping:
1 – the MFIB:
PE1#show ip mfib vrf BLUE 239.3.3.3
[...]
VRF BLUE
(*,239.3.3.3) Flags: C
SW Forwarding: 0/0/0/0, Other: 0/0/0
Tunnel0 Flags: A
Lspvif0, LSM/2 Flags: F NS
Pkts: Continue reading

There was an interesting article last week from Fastly talking about using BGP to scale their network. This was but the latest in a long line of discussions around using BGP as a transport protocol between areas of the data center, even down to the Top-of-Rack (ToR) switch level. LinkedIn made a huge splash with it a few months ago with their Project Altair solution. Now it seems company after company is racing to implement BGP as the solution to their transport woes. And all because developers have finally pulled their heads out of the sand.
BGP is a very scalable protocol. It’s used the world over to exchange routes and keep the Internet running smoothly. But it has other power as well. It can be extended to operate in other ways beyond the original specification. Unlike rigid protocols like RIP or OSPF, BGP was designed in part to be extended and expanded as needs changes. IS-IS is a very similar protocol in that respect. It can be upgraded and adjusted to work with both old and new systems at the same time. Both can be extended without the need to change protocol versions Continue reading
Cloud startups are emerging with niche solutions to make cloud computing faster, easier, and more secure.
Study provides a view into how enterprise networks are changing.
The Palo Alto User-ID feature is awesome as long as you can feed it IP-to-User mappings. PAN provides agents to do this which work in many environments, but not usually without Active Directory. I wrote RadiUID to perform this function is situations where all you have is RADIUS. Approx Reading Time: 5-15 Minutes You see, […]
The post RadiUID: Palo Alto User-ID and RADIUS appeared first on Packet Pushers.
The Palo Alto User-ID feature is awesome as long as you can feed it IP-to-User mappings. PAN provides agents to do this which work in many environments, but not usually without Active Directory. I wrote RadiUID to perform this function in situations where all you have is RADIUS. Approx Reading Time: 5-15 Minutes You see, […]
The post RadiUID: Palo Alto User-ID and RADIUS appeared first on Packet Pushers.