How the Notepad++ Breach Underlines the Value of Internal Penetration Testing

Notepad++ disclosed that its shared hosting infrastructure was compromised and attackers modified update endpoints to deliver a malicious update to targeted users between June and December 2025; the report uses this supply‑chain incident to stress that internal penetration testing is essential to identify post‑compromise attack paths (lateral movement, privilege escalation, and trust‑relationship abuses) and reduce the risk of a single compromised endpoint turning into a full internal breach.