Sometimes it's right to enjoy a more relaxed entry.
Sometimes it's right to enjoy a more relaxed entry.
A lot of people contacted me about my post on FD. No, I have no clue of what's really going and I can happily live believing the official reports (http://heartbeat.skype.com/) on the issue. This is the complete message I posted to FD in reply to Valery Marchuk (http://lists.grok.org.uk/pipermail/full-disclosure/2007-August/065343.html):
I'm sure you have already heard of the many external protocol handling vulnerabilities that hitted Firefox lately. Normally on this site you read about "in-security", this article is a little exception since it contains some tips that anybody can adopt to harden his preferred http/https client, also named Mozilla Firefox, thought the about:config interface.
Stefano Di Paola with contribution from Giorgio Fedon (both from a brand new security research company, MindedSecurity) and Elia Florio have just released the details about a Remote Code Execution flaw in Flash Plugin 9 independent from the OS. Parsing a flv with adobe flash player it's possible to trigger an exploitable integer overflow.
When exploiting XSS holes often you find yourself working around size/length and characters limitations. To avoid this type of problems a technique called "two stage payloads" comes to help. It's generally used when exploiting memory management vulnerabilities but applies to the XSS world too. The very basic idea is to have the payload divided in two parts: one that has to be injected in the entry point (PAY_ENTRY) and one that contains the actual data (PAY_DATA).
We always try to add something on topics discussed in old articles, if you liked XSS Cheat Sheet: the PLAINTEXT tag and XSS Cheat Sheet: two stage payloads perhaps you'll like this one. This article contains a more complete list of ways to avoid multiple execution of your payloads, it's a fast reading!
When performing XSS attacks often happens that the payload is displayed, and executed, multiple times occurring in unwanted and unexpected behaviors. This can be avoided in many ways, for example using global variables in JS (eg: window['started'] = true;) and checking for the variable existence at the very beginning of the payload, but when the filters are crazy and every char requires a notable effort (or when you are just hurry) one cheat gets the job done: the <PLAINTEXT> tag.
Sabato 17 Giugno a Verona presso l'Itis G. Marconi (Piazzale Guardini 1) si terra' Linuxpersec2 (Conosciamo altri modi... per proteggerlo!) con vari interventi sulla Sicurezza personale e Linux. La manifestazione e' gratuita e ovviamente siete tutti invitati :D
Today I was reading Firefox XPI Install Prevention Bypass (http://www.0x000000.com/?i=329) and while it's not what it promised to be (there is no Install Prevention Bypass) it contained useful informations that helped me elaborate two distinct thoughts.
On 30 May Mozilla Foundation announced in its MFSA (Mozilla Foundation Security Advisory) 2007-16 a bug discovered by moz_bug_r_a4 able to bypass the same-origin policy using the addEventListener helper. Needless to say you can do really nasty things by exploiting this hole, ranging from xss attacks to keystrokes logging, with no same origin limitation. If you are impatient jump directly to the demo DOM Event Keylogger.
Anurag Agarwal has published a reflection on our friend Stefano Di Paola. The interview contains a condensed auto-biography (nice reading, thanks Stefano!); integral text follows.
Yesterday I (Francesco `ascii` Ongaro) found a low impact bug: basically it is possible to make the user visit a page that is not listed in the back/next button history. The fun happens when self.location.replace() is pointing to a page that issues an HTTP/1.x 302 Redirect + Location. Both initial and redirect page will not be listed.