About
I am a Computer Science PhD candidate at Northeastern University, Boston. I'm interested in computer security, with a focus on Artificial Intelligence as a key element within a broader pipeline of components in software systems.
I am a member of the NDS2 Lab and I am fortunate to be under the joint supervision of Alina Oprea and Cristina Nita-Rotaru.
Before my PhD studies, I was an undergraduate student at the Athens University of Economics and Business, where I was a member of the MMlab. I was mentored and worked under the supervision of George C. Polyzos.
Previously, I have also been a research intern working with Yigitcan Kaya at the University of Maryland, College Park under the supervision of Tudor Dumitraș.
News
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Aug 2025
Our paper, "SAGA: A Security Architecture for Governing AI Agentic Systems", was accepted to the 2026 Network and Distributed System Security (NDSS) Symposium! See you in San Diego, CA! -
May 2025
I will be speaking at the Khoury Security and Privacy Day at Northeastern University, Boston. -
Feb 2025
I will be speaking at the New England Systems Day 2025 at Northeastern University, Boston.
Education
- Ph.D. in Computer Science
Northeastern University, present
- M.Sc. in Computer Science
Northeastern University, 2025
- B.Sc. in Computer Science
Athens University of Economics and Business, 2023
Research
The rise of AI has revolutionized the software landscape by augmenting and replacing traditional decision-making mechanisms with AI Agents that reason, plan, and act on behalf of the user. This metamorphosis in software design has transformed the security landscape in equal measure, introducing attack surfaces that were previously non-existent: agents that ingest untrusted content, make consequential decisions, and interact with other systems, all without the human judgment that traditional defenses were built to rely on.
My research develops both offensive and defensive security frameworks for AI agentic systems. On the offensive side, I have developed an automated framework that discovers indirect prompt injection attacks against web-browsing agents by identifying injection surfaces along an agent's trajectory and synthesizing context-aware adversarial payloads through execution feedback. This has uncovered dozens of end-to-end attacks, including the first demonstrated cross-application prompt injections.
On the defensive side, I have proposed a scalable security architecture for governing multi-agent systems, introducing a cryptographic mechanism for formally verified access control over agent-to-agent interactions with minimal performance overhead.
Together, these works represent a unified offensive-defensive approach to AI security: uncovering how AI systems can be compromised, and building the foundations to prevent it.
Publications
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"MUZZLE: Adaptive Agentic Red-Teaming of Web Agents Against Indirect Prompt Injection Attacks"
G. Syros, E. Rose, B. Grinstead, C. Kerschbaumer, W. Robertson, C. Nita-Rotaru, A. Oprea
preprint, Feb 2026 [PDF] -
"SAGA: A Security Architecture for Governing AI Agentic Systems"
G. Syros, A. Suri, J. Ginesin, C. Nita-Rotaru, A. Oprea
Network and Distributed System Security (NDSS) Symposium, Apr 2025 [PDF] -
"DROP: Poison Dilution via Knowledge Distillation for Federated Learning"
G. Syros, A. Suri, F. Koushanfar, C. Nita-Rotaru, A. Oprea
preprint, Feb 2024 [PDF] -
"Backdoor Attacks in Peer-to-Peer Federated Learning"
G. Syros, G. Yar, S. Boboila, C. Nita-Rotaru, A. Oprea
ACM Transactions on Privacy and Security (TOPS), Sep 2024 [PDF] -
"Decentralized NFT-based Evolvable Games"
C. Karapapas, G. Syros, I. Pittaras, G. C. Polyzos
Conference on Blockchain Research and Applications for Innovative Networks and Services (BRAINS), Sep 2022 [PDF]
Teaching
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CS3650: Computer Systems Fall 2025
Teaching Assistant at Northeastern University, Boston.
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CS6620: Fundamentals of Cloud Computing Summer 2025
Teaching Assistant at Northeastern University, Online.
Talks
- "From Autonomy to Accountability: Securing Agentic AI Systems with SAGA"
@ Khoury Security and Privacy Day, May 2025
- "DROP: Poison Dilution via Knowledge Distillation for Federated Learning"
@ NESysDay'25, Feb 2025
In the Press
- "Security of LLM Agents" [source]
@ Khoury College of Computer Sciences, Sep 2025
Software
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CookMate; developing an enhanced microwave interface with accessibility features
G. Syros, A. Toumazatos, F. Bistas Jun 2023 [PDF] [GitHub] -
Strabo.io; a real time NLP-backed Greeklish-to-Greek translation keyboard for Android
G. Syros, F. Bistas, A. Toumazatos, Jun 2023 [GitHub] -
TCP throughput over LANs and the Internet
G. Syros, A. Toumazatos, F. Bistas Feb 2023 [PDF] [GitHub1] [GitHub2]
Service
Previously, I have been a reviewer for the following venues:- ACM Transactions on Privacy and Security (TOPS)
- ACM Conference on Computer and Communications Security (CCS)
Contact
office: 5th floor, 177 Huntington Ave, Boston, MA 02115
email: syros.g at northeastern.edu
More
I play the guitar, enjoy hiking and I like anything that has an internal combustion engine (particularly 2-wheelers a.k.a. motorcycles). I am also a big supporter of Olympiacos Piraeus
.I grew up in Arachova, Greece.
Alina Oprea and I, Cybersecurity and Privacy Institute, Boston, MA
Tudor Dumitraș and I, Maryland Cybersecurity Center, College Park, MD
Me on Mt. Washington, NH
Me giving a speech at HUAWEI Hellas Enterprise 2022 scholarship ceremony, Athens, Greece
Peace and Friendship Stadium, Piraeus, Greece
Me on my motorcycle