Web Security & Privacy, Emerging Web, System Security, Computer Graphics

Ph.D. Student (ABD) in Computer Science, Georgia Institute of Technology, U.S.A.

Dual M.S. in Computer Science and Cybersecurity, Georgia Institute of Technology, U.S.A.

Sr. Software Engineer at ByteDance/TikTok Inc.

• Working on the Web Platform
• Web Standardization at the W3C CSS Working Group
• Implement WebGPU APIs in an in-house rendering engine

Intern at Igalia S.L. (cert.)

• Bring ANGLE backend for WebGL to WebKitGTK
• Zero copy texture sharing between Mesa and ANGLE via Linux DMA buffer
• Implement Text-To-Speech and Prototype Speech-To-Text for WebKitGTK (blog)

Intern at Samsung Research America

• Build a web app for health data analysis with ReactJS (frontend) and Node.js (backend)
• Built an automated system verifying the UI of a watch app by using the Tizen automation framework
• Profiled memory usage and revealed possible memory leak of a watch app by using Valgrind
• Implemented file transfer via Bluetooth LE in a React Native watch application

Software Engineer at Collabora Ltd.

• Developed hardware based compositing based on Clutter in WebKit
• Resource efficient web browser based on GNOME Epiphany for Raspberry Pi 2+
• Customized WebKit features and API set for Smart TV Alliance SDK

Jr. Software Engineer at Samsung Electronics

• Developed an in-house web layout engine for Smart TVs and printers in C++
• Implemented WebGL and Accelerated Compositing in WebKit EFL by using OpenGL ES for Tizen

Intern at Samsung Software Memembership

• Developed a 3D racing game using DirectX on Windows (video)

Instructional Associate at OMSCS, Georgia Tech

• CS 6262: Network Security

Research Intern at Tandon School of Engineering, NYU

• Explore online ad privacy issues

Teaching Assistant at the School of Computer Science, Georgia Tech

• CS 6262: Network Security, Design and Implement the XSS task using node.js and Chrome Extension
• CS 6035: Intro to InfoSec

Research Assistant at the School of Computer Science, Georgia Tech

• Study privacy leakage in online ads
• Redesign chromium to block user tracking by web browser fingerprints
• Debloat chrome browser with feature sunsetting on the fly by binary rewriting
• Developed a defense system against micro DDoS by profiling resources with HPC (Intel PCM, MBM)
• Implemented an idle profiler that diagnoses off-CPU time in the multi-threaded programs using HPC

Committer to Chromium/Blink (patch set 1, 2)

• Contributed CSS properties: font-size-adjust with the two-value syntax, FontFaceSet::check()
• Fixed many layout and rendering issues in Blink

Committer to WebKit (patches)

• Contributed CSS properties: font-size-adjust with two-value syntax, text-decoration-thickness: <length-percentage>
• Contributed several web features for WebKitGTK: Form Validation with native widgets, Gamepad API with libmanette, AVIF support with dav1d, Speech Synthesis (i.e., Text-to-Speech) with Flite, Speech Recognition (i.e., Speech-to-Text) with Whisper.cpp, etc.
• Implemented OpenGL ES backend for Accelerated Compositing
• Developed memory pressure handler that copes with out-of-memory on top of Linux cgroup
• Enhanced WebGL support and Fix layout and rendering issues
• Fixed CVE security bugs in WebKit (CVE-2020-10018, CVE-2020-11793)

Member of GNOME foundation (patches)

• Translate GNOME Web and its Help document in Korean

DeView: Confining Progressive Web Applications by Debloating Web APIs (paper)
ChangSeok Oh, Sangho Lee, Chenxiong Qian, HyungJoon Koo, and Wenke Lee

Cart-ology: Intercepting Targeted Advertising via Ad Network Identity Entanglement (paper)
ChangSeok Oh, Chris Kanich, Damon McCoy, and Paul Pearce

Slimium: Debloating the Chromium Browser with Feature Subsetting (paper)
Chenxiong Qian, HyungJoon Koo, ChangSeok Oh, Taesoo Kim, and Wenke Lee

Mitigating Low-volume DoS Attacks with Data-driven Resource Accounting (paper)
ChangSeok Oh, Sangho Lee, Wen Xu, Rohan Devang Vora, and Taesoo Kim

Web page management method and apparatus and storage medium thereof (alias Tab Group)
Worldwide applications: KR101665512B1

Interface method and display device (alias Picture-in-Picture Play)
Worldwide applications: KR101573332B1, EP2336909A3, CN102104618A

Interface method and display device
Worldwide applications: KR101630754B1

Method of re-searching webpage and apparatus and storage medium therefor (alias History Search)
Worldwide applications: KR20110128045A

ACSAC 2022 in Austin, TX, U.S.A.
DeView: Confining Progressive Web Applications by Debloating Web APIs (slides)

ACM CCS 2022 in Los Angeles, CA, U.S.A.
Cart-ology: Intercepting Targeted Advertising via Ad Network Identity Entanglement (slides)

Web Engines Hackfest 2014 in A Coruña, Spain
Raspberry Pi Browser by changseok & kov (slides)

DEVIEW 2014 in Seoul, South Korea
Lessons from developing a web browser for Raspberry Pi (slides, video)

Jeju University in Jeju, South Korea
Introduction to GNOME (slides)

DevOn 2013 in Seoul, South Korea
GNOME & You (slides)

Representative of ByteDance at W3C CSS Working Group (patches)

Mentoring student participants in the Open-source SW Developer Competition, South Korea (recognition)