Bugtraq mailing list archives
Re[2]: Regular Expression Denial of Service
From: Thierry Zoller <Thierry () zoller lu>
Date: Fri, 11 Sep 2009 19:06:09 +0200
Hi , With all due respect - this is known to be a vulnerability class since over a century. Just because it doesn't have a acronym à la XSS doesn't mean it's not known to be a vulnerability. Can we please stop the attitude of inventing acronyms for vulnerabilites, making it look like it's something new and funky. It's the impact of something that makes it a vulnerability no the name. GE> Alex Roichman wrote:
Checkmarx Research Lab presents a new attack vector on Web applications. By exploiting the Regular Expression Denial of Service (ReDoS) vulnerability an attacker can make a Web application unavailable to its intended users. ReDoS is commonly known as a “bug” in systems, but Alex Roichman and Adar Weidman from Checkmarx show how serious it is and how using this technique, various applications can be “ReDoSed”. These include, among others, Server-side of Web applications and Client-side Browsers. The art of attacking the Web by ReDoS is by finding inputs which cannot be matched by Regexes and on these Regexes a Regex-based Web systems get stuck. For further reading: http://www.checkmarx.com/NewsDetails.aspx?id=23&cat=3
GE> Alex, nice work. Thank you for sharing it with us. GE> I'd recommend taking a look at Ilja van Sprundel's work with regular GE> expression bugs in his Unusual bugs presentation. GE> ... Where he played a bit with Google Code Search back in 2007, I think. GE> He helped Google out by giving them his research, of course. GE> I found two versions online: GE> http://www.ruxcon.org.au/files/2006/unusual_bugs.pdf GE> http://www.slideshare.net/amiable_indian/unusual-bugs GE> Ilja and I later discussed creating a real regex fuzzer to discover GE> vulnerabilities, but I at least never had the time to play with it. He GE> might have, I am CC:ing him. GE> My best to Adar, GE> Gadi Evron, GE> http://www.gadievron.com/ -- http://blog.zoller.lu Thierry Zoller
Current thread:
- Regular Expression Denial of Service Alex Roichman (Sep 11)
- Re: Regular Expression Denial of Service Gadi Evron (Sep 11)
- Re[2]: Regular Expression Denial of Service Thierry Zoller (Sep 11)
- Re: Regular Expression Denial of Service Gadi Evron (Sep 11)
- Re: Re[2]: Regular Expression Denial of Service Jeffrey Walton (Sep 14)
- Re[2]: Regular Expression Denial of Service Thierry Zoller (Sep 11)
- Re: Regular Expression Denial of Service Pavel Kankovsky (Sep 14)
- Re: Regular Expression Denial of Service Pavel Kankovsky (Sep 14)
- <Possible follow-ups>
- Re: Regular Expression Denial of Service hackerwebzine (Sep 28)
- Re: Regular Expression Denial of Service Gadi Evron (Sep 11)