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Encrypting the /boot partition in a Linux system can protect from an Evil Maid Attack?

Not if the evil maid installs a hardware keylogger and steals the password you enter in GRUB to unlock the LUKS2 /boot partition.[1] However, if you have one of a few limited models of computers, you ...
2 votes

Linux x86_64 Assembly works standalone, but Segfaults when ran as shellcode in C

This line seems to describe what actually killed it. --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0xfffffffffffffffc} --- It's attempting to access something at 0xfffffffffffffffc, and ...
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0 votes

How to set iptables to drop packets that I'm not listening on?

No need for scripts; there is a suitable iptables-extensions module: socket This matches if an open TCP/UDP socket can be found by doing a socket lookup on the packet. It matches if there is an ...
3 votes

Explanation of capabilities: CAP_NET_BIND_SERVICE

Ok I understood ... Maybe it will help someone who encounters the same situation. Privileged ports numbers are registered at system level, but configurable. In my case, all TCP ports were unprivileged:...
0 votes

Sudo "/usr/sbin/halt", "/usr/sbin/reboot", "/usr/sbin/poweroff" - how to leverage it to privilege escalation?

The answer can be simple. Just like how you're doing privilege escalation by using cronjobs. You find a writable file and put your payload in then wait. sudo -l gives "/usr/sbin/halt", "...
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Do I have to block IPv4-mapped IP addresses in my IPv6 firewall?

I found a comment here You cannot use IPv4-mapped Addresses (::ffff:0:0/96) as source or destination addresses [...] Those addresses are just used to allow for an IPv4 address to be defined within ...
1 vote

How do you trust two different cloud provider servers?

In short, you mount the remote server, and then an encryption layer in top of that (such as encfs or cryfs). For example, using encfs: mkdir /mnt/server-A mkdir /mnt/server-A/insecure mkdir /mnt/...
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1 vote

Detect and remove rootkit from Debian 8.5 (x64)

A disadvantage of chkrootkit is that its algorithmics just compares against known rootkits. There is also debcheckroot ( It compares file content or sha256 sums ...
1 vote

Is it sufficient to put /var, /tmp/, and /home on their own encrypted partitions?

Sensitive data can live in lots of places. For example, /etc will contain system configuration data that might be sensitive (for example, any custom /etc/hosts entries might tell people about your ...
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0 votes

Confused about memory examination using gdb

What you're seeing is the main() prologue that is setting up the stack. It's usually identifyable from the following sequence of opcodes: push ebp mov ebp, esp sub esp, N There is a ...
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0 votes

Purpose of Real UID in spite of setresuid()

When a user launches a program/script the three types of id's (Real User ID - ruid, Effective User ID - euid, and Saved User ID - suid) would be the same. If you were to create a program that changed ...
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1 vote

Resetting LUKS password from CLI with the recovery key

The the recovery key added as part of the Ubiquity update for Debian sounds similar to what's described here if it's one that is made during initial installation of the OS. If it is, in fact, similar ...
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