About me

I am a first year PhD student Network and Information Security Lab (NISL) of Tsinghua University. My supervisor is Associate Professor Baojun Liu.

My research focuses on network security and Internet measurement, with particular interests in security of DNS and Email.

I obtained my Bachelor’s and Master’s degrees from Zhejiang Gongshang University in 2021 and 2024 respectively (advised by Professor Jun Shao). In 2025, I worked as a network security engineer at Tsinghua University.

Recent News

  1. [January 2026] Our paper about Iran Internet shutdown was accepted to WWW 2026! Congrats to Shibo!

  2. [October 2025] Our paper about email amplification attack was accepted to NDSS 2026!

  3. [August 2025] Our paper about email intermediate delivery path was accepted to IMC 2025!

  4. [July 2025] Our paper about email invisible HTML settings was accepted to ESORICS 2025! Congrats to Bingyang and Mingxuan!

  5. [September 2024] Our paper about email blocklist manipulation risk was accepted to NDSS 2025!

Selected Publications

  1. [NDSS 2025] HADES Attack: Understanding and Evaluating Manipulation Risks of Email Blocklists
  2. [IMC 2025] Understanding and Characterizing Intermediate Paths of Email Delivery: The Hidden Dependencies
  3. [WWW 2024] A Worldwide View on the Reachability of Encrypted DNS Services

Publications

2026

  1. Characterizing Iran's Phased National Internet Shutdown in 2025: A Progressive and Distributed Action

     Proceedings of ACM Web Conference (WWW), Dubai, United Arab Emirates, April 2026

    Shibo Cui, Mingxuan Liu, Baojun Liu, Haixin Duan, Ruixuan Li, Chaoyi Lu, Jin Zhang, Zhicheng Wang and Jinghua Bai

  2. CoordMail: Exploiting SMTP Timeout and Command Interaction to Coordinate Email Middleware for Convergence Amplification Attack

     Proceedings of the 33rd Network and Distributed System Security (NDSS) Symposium, San Diego, CA, USA, February 2026

    *Ruixuan Li, Chaoyi Lu, Baojun Liu, Yanzhong Lin, Qingfeng Pan, Jun Shao

2025

  1. Understanding and Characterizing Intermediate Paths of Email Delivery: The Hidden Dependencies

     Proceedings of ACM Internet Measurement Conference (IMC), Madison, Wisconsin, USA, October 2025

    *Ruixuan Li, Chaoyi Lu, Baojun Liu, Yanzhong Lin, Haixin Duan, Qingfeng Pan, and Jun Shao

  2. Email Cloaking: Deceiving Users and Spam EmailDetectors with Invisible ITML Settings

     Proceedings of the 30th European Symposium on Research in Computer Security (ESORICS), Toulouse, France, September, 2025

    *Bingyang Guo, *Mingxuan Liu, Yihui Ma, Ruixuan Li, Fan Shi, Min Zhang, Baojun Liu, Chengxi Xu, Haixin Duan, Geng Hong, Min Yang, and Qingfeng Pan

  3. HADES Attack: Understanding and Evaluating Manipulation Risks of Email Blocklists

     Proceedings of the 32nd Network and Distributed System Security (NDSS) Symposium, San Diego, CA, USA, February 2025

    *Ruixuan Li, Chaoyi Lu, Baojun Liu, Yunyi Zhang, Geng Hong, Haixin Duan, Yanzhong Lin, Qingfeng Pan, Min Yang and Jun Shao

2024

  1. Bounce in the Wild: A Deep Dive into Email Delivery Failures from a Large Email Service Provider

     Proceedings of ACM Internet Measurement Conference (IMC), Madrid, Spain, November 2024

    *Ruixuan Li, Shaodong Xiao, Baojun Liu, Yanzhong Lin, Haixin Duan, Qingfeng Pan, Jianjun Chen, Jia Zhang, Ximeng Liu, Xiuqi Lu and Jun Shao

  2. Tickets or Privacy? Understand the Ecosystem of Chinese Ticket Grabbing Apps

     Proceedings of 33rd USENIX Security Symposium (USENIX Security), Philadelphia, PA, USA, August 2024

    *Yijing Liu, Yiming Zhang, Baojun Liu, Haixin Duan, Qiang Li, Mingxuan Liu, Ruixuan Li, and Jia Yao

  3. A Worldwide View on the Reachability of Encrypted DNS Services

     Proceedings of ACM Web Conference (WWW), Singapore, May 2024

    *Ruixuan Li, Baojun Liu, Chaoyi Lu, Haixin Duan, and Jun Shao

2023

  1. A Longitudinal and Comprehensive Measurement of DNS Strict Privacy

     Proceedings of IEEE/ACM Transactions on Networking (TON), 2023

    *Ruixuan Li, Xiaofeng Jia, Zhenyong Zhang, Jun Shao, Rongxing Lu, Jingqiang Lin, Xiaoqi Jia, and Guiyi Wei

  2. The Potential Harm of Email Delivery: Investigating the HTTPS configurations of Webmail Services

     Proceedings of IEEE Transactions on Dependable and Secure Computing (TDSC), 2023

    *Ruixuan Li, Zhenyong Zhang, Jun Shao, Rongxing Lu, Xiaoqi Jia, and Guiyi Wei

MISC

Last modified: February 4, 2026