Jump to content

Hacker Technology

A group blog by Leader in Hacker Website - Providing Professional Ethical Hacking Services

  • Entries

    16114

  • Comments

    7952

  • Views

    86386616

Contributors to this blog

  • HireHackking 16114

About this blog

Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

HireHackking 
Source: https://code.google.com/p/google-security-research/issues/detail?id=546

Avast will render the commonName of X.509 certificates into an HTMLLayout frame when your MITM proxy detects a bad signature. Unbelievably, this means CN="<h1>really?!?!?</h1>" actually works, and is pretty simple to convert into remote code execution.

To verify this bug, I've attached a demo certificate for you. Please find attached key.pem, cert.pem and cert.der. Run this command to serve it from a machine with openssl:

$ sudo openssl s_server -key key.pem -cert cert.pem -accept 443

Then visit that https server from a machine with Avast installed. Click the message that appears to demonstrate launching calc.exe.

Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/38384.zip