Re: [oss] PlaidCTF - Request for participation

On Tue, Apr 16, 2013 at 10:52:36AM +0300, Razvan Deaconescu wrote: > Hi, everyone! > > Together with Lucian Cojocar & Vlad Dumitrescu (designers of the second > assignment), Irina Preșa, Adrian Șendroiu, Laura Vasilescu and Radu > Caragea (winners of DefCamp CTF), we are going to take part in the

[oss] Lab 06 - Integers

Hi, everyone! The integers lab is now online [1]. You are strongly encouraged to skim through the resources before the lab itself, especially the fourth chapter of the CERT C Coding Standard [2]. [1]: http://ocw.cs.pub.ro/courses/cns/labs/lab-06 [2]: https://www.securecoding.cert.org/confluence/

[oss] Mbox: practical and effective sandboxing for non-root users

Hi, As a continuation to the seccomp API [1], I've stumbled upon Mbox [2], a sandboxing application based on seccomp and/or ptrace. Its main advantage seems to be creating sandboxes on the fly, some audit features for applications running inside the sandbox (for files and sockets) and the ability

[oss] Unix Wildcards Gone Wild

Hi, I found the article in $subject [1] via Hacker News [2]. The examples are very interesting, as they don't exploit binary vulnerabilities, rather than a design issue of shell wildcards. I'm not sure if any of the examples there have been used for a real-life exploit, but they're instructive nev

Re: [oss] [Lab 02][Task 5] mark .data as executable

On Sat, Oct 25, 2014 at 05:06:17PM +0300, Alex Teaca wrote: > Also, I tried to compile with -S flag, and update the task5.s with > ".section .data,"awx",@progbits" > but, when I compile, I get > > gcc -C task5.s > test5.s: Assembler messages: > test5.s:5: Warning: ignoring changed section attribut

Re: [oss] [Lab 03][Task 4] volatile keyword

On Tue, Oct 28, 2014 at 02:22:57PM +0200, Alex Teaca wrote: > Hello, > > I see in get_got routine that the plt_ptr, got_min and got_max > variables are marked with the volatile keyword. > What is its purpose, is there a danger for these variables > to be modified, and the compiler don't see it ?

Re: [oss] [Assignment 1] [Task 1] no m32 compilation flag

On Tue, Nov 11, 2014 at 08:57:02AM +, Razvan Nitu wrote: > Hello all, > > When I tried to run the hasher binary I got this error [1]. I recompiled, but > i received [2]. I figured it might be the fact that I don't have the 32-bit > library so I compiled everything without the -m32 flag and e

[oss] Lab 06 - Exploit Protection Mechanisms

Hi everyone, Lab 06 is now available on the wiki [1]. [1]: http://ocw.cs.pub.ro/courses/cns/labs/lab-06 Lucian ___ http://elf.cs.pub.ro/oss/wiki/resources/mailing-list

[oss] Lab 07 - Strings

Hi everyone, The (almost) final version of Lab 7 is available on the wiki [1]. [1]: http://ocw.cs.pub.ro/courses/cns/labs/lab-07 Lucian ___ http://elf.cs.pub.ro/oss/wiki/resources/mailing-list

[oss] Lab 09 - Encryption. Hashing. APIs

Hi, everyone. A draft version of next tomorrow's lab is now available on the wiki [1]. [1]: http://ocw.cs.pub.ro/courses/cns/labs/lab-09 Lucian ___ http://elf.cs.pub.ro/oss/wiki/resources/mailing-list

[oss] Analysis of XKCD's "Password Strength" comic

Hi, The guys on the security Stack Exchange site have started a discussion [1] on XKCD's "Password Strength" comic [2]. One of the answers [3] in particular provides a more detailed analysis of the choices and underlying assumptions made by the author to show that the passphrase approach is actual

[oss] Lab 10 - Password Breaking

Hi everyone, A draft of Lab 10 is now available on the wiki [1]. [1]: http://ocw.cs.pub.ro/courses/cns/labs/lab-10 Lucian ___ http://elf.cs.pub.ro/oss/wiki/resources/mailing-list

Re: [oss] Assignment 3

On Fri, Jan 09, 2015 at 11:18:24PM +0200, Alexandru Tudorica wrote: > On Thu, Jan 8, 2015 at 11:33 PM, Radu Caragea wrote: > I'm getting the mails from yahoo into spam (I'm using Gmail). Can somebody > fix the mailing list configuration? Hi, Unfortunately this is an issue that affects all the li

[oss] xchg rax, rax

Hi, everyone! As most of you should be comfortable with x86 assembly by now, I thought I'd share the book/collection mentioned in $subject. xchg rax, rax [1] is a collection of riddles written in assembly, most of which rely heavily on the various behaviours documented in the x86 instruction set.

[oss] Lab 11 - Web Application Security (part 1)

Hi, Lab 11 is up on the wiki [1]. See you at the lab! [1]: http://ocw.cs.pub.ro/courses/cns/labs/lab-11 Lucian ___ http://elf.cs.pub.ro/oss/wiki/resources/mailing-list

[oss] Lab 12 - Web Application Security (part 2)

Hi everyone, Lab 12 is now available on the wiki [1]. [1]: http://ocw.cs.pub.ro/courses/cns/labs/lab-12 Lucian ___ http://elf.cs.pub.ro/oss/wiki/resources/mailing-list

[oss] Using symbolic execution for reverse engineering

Hi everyone, ctfhacker.com has a post on combining radare2 and symbolic execution to reverse engineer a CTF binary [1]. You might remember radare2 from the first labs. Although its interface is a bit clunky, the post shows a few interesting uses in the preliminary stages of reversing. For those o

Re: [oss] [cns] [vm] down?

On Tue, Jan 05, 2016 at 12:29:13PM +0200, Teodora Olaru wrote: > ssh: connect to host 141.85.227.139 port 12322: Network is unreachable Hi Teodora, I tried accessing your address:port from multiple places and it worked for me. Do you have any outbound ports blocked from your location? Lucian ___

[oss] RHme2 challenge

Hi everyone, Riscure are organizing Riscure Hack me 2 [1], a CTF contest aimed at low-level hardware hacking. To qualify, the contestants must find the flag in a binary file, very similarly to Răzvan's demo at the first CNS lecture. A limited number of boards are available to be shipped to the co

[oss] Kali Linux Virtual Machine

Hi everyone, You may now download an official(tm) CNS-approved(c)(r) virtual machine from the resources directory linked on the wiki [1]. The VM uses Kali Linux, a security-oriented distro that contains all the pwning tools you will need for the CNS class (and more!). We recommend it as a referen

Re: [oss] Tool to add symbols back to a stripped binary

Vladimir Oltean writes: > Hi, > > Yesterday I wrote this Bash helper script as a wrapper around "objcopy > --add-symbol". [1] Nice job, Vladimir! It looks very cool! > [1]: > https://github.com/vladimiroltean/blog/blob/master/dotfiles/bin/apply-symbols Lucian ___

[oss] Computer and Network Security, moving forward

Hi everyone, As discussed today at the lecture, there are a few ways for those of you who liked the CNS class to further explore the field. One way is to play wargames: IO/NetGarage [1] (some of the levels there we've already explored in the labs), Smashthestack [2], WeChall [3], Embedded Securit

Re: [oss] Computer and Network Security, moving forward

Lucian Mogosanu writes: > Hi everyone, > > As discussed today at the lecture, there are a few ways for those of you > who liked the CNS class to further explore the field. *snip* > If you have any further questions about this, don't hesitate to keep the > discussion g