The democratization of artificial intelligence has made substantial progress by leveraging open-source large language models (LLMs), enabling researchers across domains to train customized models to meet their specific needs. Given the confidentiality and significance of cybersecurity, obtaining private and localized LLMs is imperative. However, general LLMs are not designed to cater specifically to this field, their general knowledge often falls short when addressing such specialized problems. In this paper, we categorize the domain instructions based on cybersecurity knowledge to guide the construction of high-quality instructions and conversations, ultimately enhancing the specialized capabilities of LLMs. The resulting fine-tuned LLMs, collectively termed HackMentor, are evaluated using WinRate, EloRating, and ZenoEval methods along with other popular LLMs. The experiments demonstrate that the proposed method yields significant performance improvements, surpassing the native LLMs by 10-25% when aligned with cybersecurity prompts. More, HackMentor exhibits comparable conversational quality to ChatGPT, while providing more concise and humanlike responses. This study demonstrates the efficacy of HackMentor in augmenting LLMs for cybersecurity requirements, paving the way for localized LLMs that meet specialized needs without compromising general capabilities.