Coldcard Firmware Exploit (2026)

1 March 2021

A commit attributed by researcher James O'Beirne to Coinkite CTO Peter Gray (via GPG signature) replaces a hardware RNG call with MicroPython's Yasmarang software PRNG in the libNgU library, introducing the entropy vulnerability.

17 March 2021

Coldcard firmware version 4.0.1 is publicly released, incorporating the vulnerable seed generation path. Affected devices begin generating seeds with reduced entropy.

1 May 2025

Bitcoin developer James O'Beirne reportedly flags the flawed randomness code to Coinkite after auditing the firmware repository, describing libNgU as a low-star, single-maintainer dependency. According to O'Beirne, Coinkite responded that the issue would likely have surfaced by now if real. Coinkite has not publicly confirmed or denied this account.

30 July 2026

First attack wave begins. Attackers drain approximately 594 BTC (~$38 million) from roughly 500 addresses in approximately 25 minutes (first reporting figure). Separately, Hacker News and TRM report 1,082.65 BTC removed from 1,196 addresses in 41 minutes — the discrepancy reflects differing wave-boundary definitions.

30 July 2026

Coinkite publishes its security advisory disclosing the vulnerability, directing all users who generated seeds on affected firmware to migrate funds immediately.

31 July 2026

Coinkite ships emergency patched firmware: version 5.6.1 for Mk4/Mk5 and 1.5.1Q for the Coldcard Q. Patched firmware requires user-supplied entropy for new seed generation. Existing seeds remain compromised.

1 August 2026

Coinkite updates its security advisory with additional technical detail. Attack waves continue.

2 August 2026

Galaxy Research identifies a third attack wave, with cumulative losses reaching 1,367 BTC (~$88.6 million) across 4,585 addresses.

4 August 2026

Forbes and TechCrunch publish wider-audience coverage. TRM Labs reports minimal laundering activity: 64.9 BTC to Wasabi CoinJoin and minimal ETH-side movement.

6 August 2026

No confirmed new attack activity observed after this date, according to Galaxy Research.

6 August 2026

WeirFoulds LLP (Toronto) publishes legal analysis of victim recovery options, noting class-action litigation against Coinkite was being organized. No formal filing reported.

9 August 2026

Cryptopolitan and others report O'Beirne's GPG-based attribution of the vulnerable commit to Peter Gray, Coinkite CTO. Coinkite does not publicly respond to the attribution.

14 August 2026

Galaxy Research report confirms 1,778 BTC stolen (~$112 million at theft prices) across 8,865+ addresses.

15 August 2026

Galaxy Research publishes assessment that attackers likely used unrestricted AI models (citing Kimi K3 as an example) to discover and exploit the vulnerability, based on circumstantial analysis of attack sophistication. Assessed as speculative rather than forensically proven.

24 August 2026

Galaxy Research updates final estimate to 1,789.28 BTC stolen across 8,865 addresses ($114.7 million at time of theft, approximately $138.8 million at then-current prices).

7 September 2026

Approximately 82% of stolen Bitcoin reported as still frozen in attacker-controlled wallets. Approximately $7.8 million laundered through THORChain and CoinJoin. No new attack waves or criminal charges reported.