Polkadot Foundation Warns of Fearless Extension Risk Involving 17,286 DOT

The Polkadot community foundation warned that four Fearless browser extension versions may have exposed users’ private keys, after reports of unauthorized transactions involving 17,286 Polkadot (DOT).

Eight users reported transactions that appeared connected to the issue. The warning names releases 3.0.1, 3.0.3, 3.0.4 and 3.0.5.

The foundation said malicious code in those versions could send a user’s private key to a server controlled by attackers when the wallet was unlocked. The unlock step is the exposure point described in the warning.

The code’s active periods differed by version. Across the releases, activity ran from February 2025 through Oct. 10, 2026. That span covers separate activation windows, not one continuous run for every version.

The 17,286 DOT figure refers to funds involved in the reported unauthorized transactions. Fearless is a third-party wallet, and the warning focuses on its browser extension releases.