Suji Yan Mask Network Founder Mobile Wallet Birthday Theft

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Mask Network Yuji San

Suji Yan, founder and CEO of Mask Network, is a leading voice in the Web3 space. With a background in journalism and computer engineering, Suji has been a vocal advocate for privacy, digital sovereignty, and user empowerment. In 2022, he also launched Bonfire Union, a venture fund supporting overlooked founders in the decentralized tech ecosystem. On his 29th birthday, Suji reported a security breach where over $4 million in crypto assets were stolen from a wallet he managed via mobile phone. He suspects an offline attack may have occurred when his phone was briefly unattended during a private gathering. Despite immediate coordination with security experts and blockchain investigators, the funds—spread across multiple tokens like ETH, WETH, MASK, and USDT—have not been recovered.

About Suji Yan

Suji Yan is a prominent entrepreneur and advocate for decentralized technologies and digital privacy. As the founder and CEO of Mask Network, he is best known for pioneering the integration of Web3 features into Web2 social platforms, allowing users to interact with decentralized applications, encrypt messages, and manage assets—all from within familiar interfaces like X (formerly Twitter) and Facebook.

Born in China, Suji Yan studied Computer Engineering at the University of Illinois Urbana-Champaign and briefly attended the University of Tokyo before dropping out to pursue entrepreneurship in 2017. Before founding his company, he worked as an independent journalist for outlets such as Caixin and Qdaily, where he developed a deep interest in AI, cryptocurrencies, and digital freedom.

Suji is a frequent speaker at blockchain and privacy-focused events, sharing his views on digital sovereignty, decentralized governance, and the importance of user-controlled systems. He envisions Mask as the "bridge" between the closed ecosystems of Web2 and the open potential of Web3, much like how DeFi disrupted traditional finance.

In 2022, Suji founded Bonfire Union, a venture capital initiative supporting underestimated founders in the Web3 space. He has also donated to institutions such as UIUC and RadicalxChange, supporting research and civic dialogue. Alongside his wife Katt Gu, Suji co-launched the anti-996 campaign, advocating for healthier work-life balance in tech.

Suji has received numerous accolades, including the JASSO Scholarship and awards from Hackathons hosted by Google and Intel. His early projects range from operating systems and weather apps to decentralized tech experiments. Notably, he has invested in or partnered with over a dozen Web3 ventures, including Soul Wallet, Transak, and 0xPPL.

Today, Suji leads Mask Network and serves as a board member at RSS3, continuing to expand the decentralized social internet. With a focus on user empowerment, privacy, and open-source collaboration, he remains a key figure in shaping the future of online interaction and digital identity.

About Mask Network

Maintained by Dimension since 2019, Mask Network is a free, open-source project committed to building a secure and inclusive decentralized internet. The team invites developers and users alike to contribute and explore a new digital dimension together.

Launched in 2017, Mask Network received early funding from notable investors like Li Toyo. The platform has since grown into a robust suite of Web3 tools including encrypted posting, token swaps, decentralized identity, and NFT rendering—offering users a secure and user-friendly entry point into the decentralized web. Suji's work continues to challenge centralized social media by advocating for a layered approach to Web3 adoption rather than mass user migration.

Mask Network is a browser extension that bridges Web2 and Web3, allowing users to access encrypted messaging, decentralized profiles, and other Web3 services directly within social media platforms like X (formerly Twitter), Facebook, Instagram, Minds, and Mirror. It lets users enjoy traditional social media while seamlessly tapping into blockchain-based functionalities.

With Mask Network, users can experience features such as encrypted posts, NFT rendering, Snapshot voting, Gitcoin funding, Web3 file sharing, and scam warnings—directly in their social feeds. It transforms NFT links into interactive cards and supports tools like ENS search, token and NFT lookup, and integrated calendars.

Through the Next.ID protocol, Mask integrates decentralized identity verification, asset management, and wallet controls in a secure, cross-platform plugin. Its open-source, multi-chain wallet supports over 15 major EVM chains and offers asset tracking, token swaps, and dApp gateways—all in one interface.

Mask supports innovative Web3 apps like Lucky Drop (viral social giveaways), Smart Pay (Polygon-based contract wallet using Mask Token for gas), Web3 file storage (IPFS & Arweave), decentralized exchanges, ETH/stablecoin savings, wallet approval management, and fiat on-ramps for over 60 currencies.

Mask Network integrates with 30+ major Web3 projects and services including CoinGecko, ENS, Gitcoin, Snapshot, IPFS, OpenSea, Firefly, and Lens. It also supports leading wallets and chains, continually expanding its ecosystem.

The Reality

Suji Yan was managing a large $4m+ wallet via his mobile phone.

What Happened

Suji Yan, founder of the Mask Network, lost over $4 million in cryptocurrency due to a suspected wallet hack.

Key Event Timeline - Suji Yan Mask Network Founder Mobile Wallet Birthday Theft

Date	Event	Description
February 26th, 2025 8:20:00 AM MST	Yuji San ByBit Retweet	Yuji San retweets information about the ByBit hack.
February 27th, 2025 2:49:59 AM MST	Transfer Of Wrapped Ethereum	923.817499554962882 wrapped ethereum are transfered from Suji Yan's wallet to the attacker.
February 27th, 2025 3:00:23 AM MST	Transfer Of Ethereum	113.063816357204803291 ethereum are transfered from Suji Yan's wallet to the attacker.
February 27th, 2025 5:31:00 AM MST	Cyvers Alerts Tweet Posted	Cyvers Alert posts that their AI-powered system has detected suspicious transactions involving Suji Yan, founder of @realMaskNetwork. Nearly $4 million in digital assets—including ETH, WETH, ezETH, weETH, pufET, MASK, USDT, and swETH—were sent to a suspicious address, then quickly swapped to ETH and distributed across six different wallets. Cyvers credits @zachxbt for swift and effective coordination in response to the incident.
February 27th, 2025 6:25:00 AM MST	Yuji San Tweet Posted	Yuji San posts that on his 29th birthday, a public wallet on his phone was hacked, resulting in the theft of over $4 million in assets across a series of manual transactions over 11 minutes. He suspects either a same-day key leak or a possible offline attack during a private gathering. Investigations are underway with the help of @SlowMist_Team, @zachxbt, and relevant authorities. Yuji urges transparency, stating that if this was an offline betrayal, the perpetrator should come forward—emphasizing that crypto should not remain a dark forest. The same post is made in Chinese several minutes later.
February 27th, 2025 6:51:00 AM MST	Yuji San Getting Philosophical	Yuji San expands on the Chinese translation of his post to add that he appreciates the public’s concern but urges everyone to remain rational and avoid speculation. While an offline attack is one possibility, he hopes it was not carried out by anyone he knows and has already brought in professionals to investigate. He clarifies that the stolen funds are his personal assets and have no connection to his company, its funds, or any affiliated projects—so there is no cause for concern on the business side. He ends with classical Chinese reflections on enduring hardship and personal growth in the face of adversity.
February 27th, 2025 11:18:00 AM MST	Yuji San News Algorithm	Suji Yan comments on how their story is appearing high in their news feed.
February 27th, 2025 12:54:00 PM MST	Web3IsGoingGreat Post	Web3IsGoingGreat posts about the incident: Suji Yan, founder of the Mask Network, lost over $4 million in cryptocurrency due to a suspected wallet hack. The theft occurred on his birthday while he was attending a private party, leading Yan to speculate that his private key may have been leaked or that the hack was executed through an offline attack during a brief moment when his phone was unattended.
February 28th, 2025 2:56:00 AM MST	Suji Yan On FireFly	Suji Yan posts an update related to the FireFly application, noting that the recent incident has driven the highest traffic the team has seen in the past year, with rapid growth. He clarifies that the stolen funds were his personal assets and not connected to company products, which remain secure. He encourages users to try out FireFly, emphasizes the platform’s strong security in the social space, and humbly acknowledges the need to improve his own security practices. He ends by calling for continued support for $MASK and @thefireflyapp.
February 28th, 2025 8:59:00 PM MST	Untitled Event	Suji Yan mentions the hack in a Tweet about meeting governor Terry Branstad.
February 28th, 2025 10:12:47 PM MST	Yuji San Messages Hacker	Yuji San sends a message to the hacker on the Ethereum blockchain warning that an international coalition involving the FBI, Hong Kong police, Interpol, and private security has identified and is actively pursuing them. The hacker is reportedly fully doxxed. The hacker is being provided a timeline of 72 hours to return the stolen funds and allowed a generous bounty. This is apparently the hacker’s only chance to walk away with anything—time is running out.
March 1st, 2025 4:21:00 PM MST	Yuji San Message	Wu Blockchain reports an on-chain message to the hacker "The FBI, Hong Kong police, Interpol, and private security personnel are working together and have identified and are pursuing you. Evidence of your actions has been obtained by us and our law enforcement partners. You have 72 hours to return the stolen funds before the situation escalates beyond control. Once the funds are returned, we will cease all tracking, destroy the collected data, and close the case. If you comply within this timeframe, we are willing to offer a generous bounty as a resolution reward."

Technical Details

Yuji San believes that there may have been an in-person attack on their mobile wallet, when they left their phone unattended during their birthday party.

Total Amount Lost

Widely reported at $4m.

Assets reported by Cyvers: "113 $ETH 923 $WETH 301 $ezETH 156 $weETH 90 $pufET 48.4K $MASK 50K $USDT 15 $swETH"

113 $ETH 113 2,237.91 252883.83 923 $WETH 923 2,237.91 2065590.93 301 $ezETH 301 2,237.91 673610.91 156 $weETH 156 2,237.91 349113.96 90 $pufETH 90 2,237.91 201411.9 48.4K $MASK 48400 2.2169 107297.96 50K $USDT 50000 1 50000 15 $swETH 15 2,237.91 33568.65 3733478.14

The total amount lost has been estimated at $3,733,000 USD.

Immediate Reactions

Yuji San posted a summary of the event on Twitter:

"I turned 29 yrs old today, 6 hours ago. Around 3 hours ago - one of my public wallet I carried on my phone was hacked and 4m$+ assets was stolen. All the stolen tx seems manual and span 11+ mins.

So either the private key was leaked same day as my birthday and hacker manual tsf out or it might be an offline attack. I was in a private gathering with dozen friends and my phone was away for some minutes when I using the restroom etc. I trust my friends but this is a nightmare to anyone.

I’ve contacted @SlowMist_Team and @zachxbt to help the investigation and in cooperation with authorities and agencies. Before there are any outcome from these experts I will not say more.

I hope if this is the offline case - you should confront me directly. Crypto is not a dark forest and I will not let it be."

Ultimate Outcome

It does not appear that there is any update.

Total Amount Recovered

It is believed that the funds were not recovered.

There do not appear to have been any funds recovered in this case.

Ongoing Developments

What parts of this case are still remaining to be concluded?

Individual Prevention Policies

No specific policies for individual prevention have yet been identified in this case.

For the full list of how to protect your funds as an individual, check our Prevention Policies for Individuals guide.

Platform Prevention Policies

Policies for platforms to take to prevent this situation have not yet been selected in this case.

For the full list of how to protect your funds as a financial service, check our Prevention Policies for Platforms guide.

Regulatory Prevention Policies

No specific regulatory policies have yet been identified in this case.

For the full list of regulatory policies that can prevent loss, check our Prevention Policies for Regulators guide.