Umbra has taken its front-end website offline after detecting around $800,000 in stolen funds moving through its protocol linked to recent high-profile crypto hacks.
The shutdown follows the $280 million exploit of Kelp, with reports suggesting attackers attempted to route funds through Umbra to bridge assets between blockchains.
Umbra said it placed its hosted interface into maintenance mode to avoid interfering with recovery efforts and would restore access once it no longer poses a risk.
The protocol stressed it cannot prevent usage of its underlying smart contracts or alternative self-hosted front ends due to its open-source design.
“Nothing we can do to stop users interacting directly with the contracts or deploying their own interface,”
The team said, while noting the tool is designed to protect receiver privacy rather than obscure sender activity.
Roman Storm warned the move may not shield developers from legal scrutiny, arguing authorities could still view front-end control as equivalent to protocol control.
Storm, previously convicted over his role in Tornado Cash, said prosecutors treated interface changes as evidence of operational control, highlighting ongoing regulatory pressure on privacy tools in crypto.