Jameson Lopp warns Bitcoin holders against giving up self custody

Casa chief security officer Jameson Lopp has urged Bitcoin holders not to abandon self custody in favor of ETFs and third party custodians following a series of cryptocurrency wallet security incidents.

In an October 22 open letter addressed to Casa clients and the Bitcoin community, Lopp argued that recent attacks had raised genuine concerns about managing private keys but did not justify giving up direct control of Bitcoin holdings.

Lopp pointed to recent incidents involving hackers using AI to find security flaws, compromised hardware wallet supply chains, drained cold wallets and more sophisticated scams, which have left many Bitcoin holders questioning whether they can safely manage their own funds.

According to him, many of the attacks making headlines today were already known to security professionals, although their emergence in actual incidents had made the risks more difficult for ordinary holders to ignore.

Lopp warns Bitcoin ETFs do not eliminate custody risks

Lopp took particular issue with the idea that moving Bitcoin into exchange traded funds or other managed custody arrangements offered a straightforward solution to recent security problems.

He acknowledged that investors could feel more comfortable relying on financial institutions after hearing about wallet compromises, but argued that transferring control of private keys merely placed responsibility with another party.

In his view, Bitcoin ETFs provide investors with exposure to the cryptocurrency’s price without giving them direct control over the underlying coins.

The arrangement requires investors to depend on the fund, its custodian and other parties responsible for safeguarding the assets. Lopp warned that holders could have little influence over decisions affecting their Bitcoin, including situations involving freezes or seizures by authorities.

He maintained that Bitcoin’s defining properties came from its fixed supply, publicly verifiable rules and the ability of users to access their holdings without obtaining permission from an intermediary.

Although investors could benefit financially from Bitcoin without holding private keys, Lopp argued that they would not enjoy the same degree of control available through direct ownership.

The warning followed reports that some Bitcoin holders had moved assets toward centralized platforms after recent wallet compromises.

In August, crypto.news reported record OKX inflows following the Coldcard hardware wallet exploit, with the exchange saying that customers were increasingly turning toward managed custody.

Recent Bitcoin wallet exploits have raised security concerns

The concerns outlined in Lopp’s letter followed several incidents involving weaknesses in wallet software, hardware distribution and private key generation.

One of the most significant cases involved Coldcard hardware wallets, where a firmware configuration error dating back to March 2021 caused affected devices to generate recovery seeds using a weaker source of randomness.

An August 3 report on the Coldcard security exploit detailed suspected Bitcoin thefts worth nearly $90 million at the time and calls from Kraken chief security officer Nick Percoco for independent testing of wallet seed generation.

The flaw allowed attackers to reconstruct vulnerable private keys without physically accessing the devices or obtaining their recovery phrases.

Coldcard subsequently released corrected firmware, although previously generated vulnerable seeds required users to create new wallets and transfer their holdings.

More recently, an October 13 investigation into compromised Ledger hardware wallets detailed cases involving devices distributed through Southeast Asian reseller CryptoBilis.

Ledger confirmed that an unauthorized hardware implant had been identified in one affected device, while the investigation had not established that its own systems or direct sales channels were compromised.

Security problems involving weak recovery seeds have affected other cryptocurrency networks as well.

On October 18, Qubic disclosed a wallet security breach involving approximately 2.94 trillion QU tokens worth $1.4 million stolen from 1,404 wallets.

Developers traced the incident to insufficient randomness in certain wallet recovery seeds and subsequently corrected the affected software.

Multisig security remains central

Against this background, Lopp argued that the response to failed security controls should involve improving wallet protection instead of abandoning self custody altogether.

Drawing on more than 15 years of security incidents across the cryptocurrency industry, he said effective custody arrangements needed to account for human mistakes and the possibility that individual safeguards could fail.

His preferred approach involved multisignature wallets, which distribute transaction authorization across multiple private keys and can prevent a single compromised key from providing complete access to funds.

Lopp cautioned that multisig was not a complete solution by itself, although he maintained that carefully designed arrangements could provide stronger protection than conventional custody systems.

He encouraged Bitcoin holders to review their existing setups and distribute keys across different geographic locations and hardware supply chains to reduce their dependence on any single device or location.

The letter addressed inheritance planning as another important consideration, particularly what would happen to someone’s Bitcoin if they became unable to access or manage their holdings.

Casa, which provides assisted self custody services, positions its role around helping customers manage these arrangements without taking possession of their private keys.

Lopp closed by warning that both malicious actors and well intentioned intermediaries could ultimately gain control over someone else’s Bitcoin, leaving holders responsible for deciding how much control they were prepared to surrender.