Zuoguang Wang

Peipei Liu, Hong Li, Zuoguang Wang et al.

Extracting cybersecurity entities such as attackers and vulnerabilities from unstructured network texts is an important part of security analysis. However, the sparsity of intelligence data resulted from the higher frequency variations and the randomness of cybersecurity entity names makes it difficult for current methods to perform well in extracting security-related concepts and entities. To this end, we propose a semantic augmentation method which incorporates different linguistic features to enrich the representation of input tokens to detect and classify the cybersecurity names over unstructured text. In particular, we encode and aggregate the constituent feature, morphological feature and part of speech feature for each input token to improve the robustness of the method. More than that, a token gets augmented semantic information from its most similar K words in cybersecurity domain corpus where an attentive module is leveraged to weigh differences of the words, and from contextual clues based on a large-scale general field corpus. We have conducted experiments on the cybersecurity datasets DNRTI and MalwareTextDB, and the results demonstrate the effectiveness of the proposed method.

Zuoguang Wang, Jiaqian Peng, Hongsong Zhu et al.

This paper proposes an authentication-simplified and deceptive scheme (SEIGuard) to protect server-side social engineering information (SEI) and other information against brute-force attacks. In SEIGuard, the password check in authentication is omitted and this design is further combined with the SEI encryption design using honey encryption. The login password merely serves as a temporary key to encrypt SEI and there is no password plaintext or ciphertext stored in the database. During the login, the server doesn't check the login passwords, correct passwords decrypt ciphertexts to be correct plaintexts; incorrect passwords decrypt ciphertexts to be phony but plausible-looking plaintexts (sampled from the same distribution). And these two situations share the same undifferentiated backend procedures. This scheme eliminates the anchor that both online and offline brute-force attacks depending on. Furthermore, this paper presents four SEIGuard scheme designs and algorithms for 4 typical social engineering information objects (mobile phone number, identification number, email address, personal name), which represent 4 different types of message space, i.e. 1) limited and uniformly distributed, 2) limited, complex and uniformly distributed, 3) unlimited and uniformly distributed, 4) unlimited and non-uniformly distributed message space. Specially, we propose multiple small mapping files strategies, binary search algorithms, two-part HE (DTE) design and incremental mapping files solutions for the applications of SEIGuard scheme. Finally, this paper develops the SEIGuard system based on the proposed schemes, designs and algorithms. Experiment result shows that the SEIGuard scheme can effectively protect server-side SEI against brute-force attacks, and SEIGuard also has an impressive real-time response performance that is better than conventional PBE server scheme and HE encryption/decryption.