8 posts found
5 min read
A noisy capture with one loud port scan hiding the real story. Filtering the noise exposes a WordPress Social Warfare exploit, the HTTP port the attacker served the payload from, and the reverse shell that called home — exactly the two ports the flag wants.
#CTF#Cybersecurity#Network
3 min read
A full 65535-port TCP SYN sweep from 192.168.1.104 against 192.168.1.102: classify every response into SYN-ACK (open) versus RST (closed) and the target exposes exactly two open ports.
#CTF#Cybersecurity#Network
4 min read
A Cisco Packet Tracer .pkt file with no magic header and an encrypted body holds a hidden Shakespeare Programming Language program; decrypt the container, find Borring novel.txt, run it, and recover the master key.
#CTF#Cybersecurity#Network
4 min read
An old IoT device SSHv2 session captured in a pcap, encrypted with AES-128-CBC. The 2007-era Debian OpenSSL weak PRNG (CVE-2008-0166) makes the Diffie-Hellman private exponent recoverable, so the whole session can be decrypted and the flag read off the wire.
#CTF#Cybersecurity#Network
3 min read
A packet capture of an intrusion against a vsftpd 2.3.4 server. The attacker pops the famous smiley backdoor, lands a root shell, then exfiltrates a JPEG as base64 over a reverse shell. Reassemble the stream and the flag is painted inside the stolen image.
#CTF#Cybersecurity#Forensics
4 min read
A pcap posing as a Bluetooth file transfer actually carries a WAV file split across 459 UDP packets. The audio is not a protocol — it is a Hellschreiber bitmap, and the spectrogram is the decoder.
#CTF#Cybersecurity#Forensics
3 min read
A tiny capture that looks like DNS noise, a decoy ICMP flood and a fake SSH session. The real message is smuggled in two header fields nobody reads: the IP identification field of ICMP echoes and the TCP window size of an HTTP flow.
#CTF#Cybersecurity#Forensics
4 min read
A packet capture of a data-exfiltration implant that steals images off a Windows desktop, XORs them with a hard-coded key and POSTs them as hex. The served malware ships the key, so the whole capture decrypts back to the stolen files.
#CTF#Cybersecurity#Forensics