25th October, 2019
1 Min read
Two academics from the Technical University of Cologne (TH Koln) have disclosed this week a new type of web attack that can poison content delivery networks (CDNs) into caching and then serving error pages instead of legitimate websites.
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The new attack has been named CPDoS (Cache-Poisoned Denial-of-Service), has three variants, and has been deemed practical in the real world (unlike most other web cache attacks).
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HOW CPDOS ATTACKS WORK
CPDoS attacks are aimed at two components of the modern web — (1) web servers and (2) content delivery networks.
Web servers store the original website and its content, while CDNs store a cached copy of the website that is only refreshed at certain time intervals.
Despite their simplistic role, CDNs are a crucial part of the modern internet, as they can alleviate the load on web servers. Instead of a web server computing the same user request over and over again, a CDN can provide some of the incoming users with a copy of the website, until the CDN refreshes itself with a new version.
CDNs are widey used. Any attack on a CDN system can have devastating consequences on a website’s availability, and, hence, it’s profitability.
Read more: ZDnet.com