COLDCARD firmware

This commit adds a new feature to the COLDCARD firmware: encrypted backups for Secure Notes & Passwords. Previously, exporting notes and passwords to a microSD card produced an unencrypted JSON file. Now the device can encrypt that export using the same 7z/AES backup encryption used for full wallet backups. The change also refactors the existing backup password code so it can be reused for both full-device and notes-only backups. A small, unrelated fix in message signing changes a logical AND to an OR when deciding whether tab/newline characters are allowed in signed text. There is no vendor disclosure of a security vulnerability, and the commit is framed as a feature addition.

This commit reverts a previous security fix. The original fix prevented a 'bypass PIN' (a special trick PIN that hides the wallet) from being used a second time to finish logging in without ever entering the real main PIN. After this revert, entering the bypass PIN again at the second prompt will complete login into an empty, no-secret session, just as it did before the fix. The change also removes the bugfix note from the changelog and updates tests to expect the old, less restrictive behavior again.

This commit adds a new feature to the COLDCARD hardware wallet that lets users apply the text of a Secure Note or the value of a Secure Note password as their BIP-39 wallet passphrase. It also tightens how printable ASCII is checked in a few places. The change is user-facing and requires physical interaction, so it does not look like a remote exploit. However, because passphrases control which wallet is derived, any bug in how note text is sanitized or applied could cause a user to load an unexpected wallet or expose a note's contents as a passphrase.

This commit fixes a bug in the COLDCARD Q1 hardware wallet where displaying certain QR codes containing non-English or special characters could cause the device to crash with an assertion failure. The fix ensures text is converted to UTF-8 bytes before calculating QR code sizes, preventing a mismatch between expected and actual data length. There is no direct evidence this bug is exploitable for malicious purposes.

This commit adds a new feature to the COLDCARD firmware that lets users organize their saved secure notes and passwords into groups, similar to folders. It is a user-experience improvement and does not fix or introduce any security vulnerability.

This commit fixes several bugs in how the COLDCARD Q1 hardware wallet talks to its built-in QR-code scanner. The changes make scanner startup more reliable, prevent stale 'go to sleep' commands from accidentally stopping a scan that just started, and recover better when commands time out or the user cancels. The changelog calls these 'Scanner robustness' fixes. There is no direct evidence this is a security vulnerability that can be exploited by an attacker; it is primarily a reliability/stability improvement. However, because the QR scanner is used to read sensitive data such as Bitcoin transactions and seed backups, any crash or misbehavior during scanning could in theory affect user funds or cause denial of service, so the change has defensive-security value.

This tiny code change moves a 'needs reinit' flag from being shared across all QR scanner objects to being kept inside each individual scanner object. In the real device code the flag is removed from the base class; in the simulator it is added as an instance variable. The change is a bug-fix style cleanup that prevents scanner state from leaking between different scanner instances. There is no direct evidence in the commit of a security vulnerability, but shared mutable state can in principle cause race-condition or state-confusion bugs.

This commit fixes a bug in how the COLDCARD wallet creates encrypted backups when a temporary seed is being bypassed. Previously, if the main secret was stored as an extended private key ('xprv') rather than as BIP39 seed words, the backup code could incorrectly encode the secret and potentially return to or expose the master secret in the wrong form. The fix ensures the correct secret type is used when restoring settings from the main seed during backup generation.

This commit only updates two test files to fix failing tests. It changes test input data and adds an address-format parameter that a helper function now requires. There is no change to the actual COLDCARD firmware or wallet code that users rely on, so it does not affect device security.

This commit fixes a bug in the COLDCARD hardware wallet that prevented it from correctly signing Bitcoin transactions that spend from 'pay-to-public-key' (P2PK) outputs. P2PK is an older, uncommon output type where coins are locked directly to a public key rather than to a Bitcoin address. The bug meant P2PK signing was broken entirely, and the device could not handle both compressed (33-byte) and uncompressed (65-byte) public key forms. The fix updates the firmware to recognize both key lengths, compare them correctly against derived keys, and produce the right transaction signature format. It also adds tests that exercise real P2PK spends against Bitcoin Core.

This update fixes a bug in the COLDCARD hardware wallet where a malicious or malformed Bitcoin transaction file (PSBT) could trick the device into using the wrong amount of money for a non-SegWit (legacy) input. Specifically, if the file only provided a lightweight 'witness UTXO' for a legacy input, the device would trust that amount. An attacker could lie about the amount, making the transaction look like it had a normal fee when it actually sent much more to the miner or another recipient. The fix rejects such files for legacy inputs, prefers the full previous transaction when both types are present, and suppresses fee calculation when a witness-only UTXO cannot be verified as genuinely SegWit.

This commit tightens input-length checks for commands that COLDCARD receives over its USB interface. Before the change, several commands would accept packets that were too short, too long, or internally inconsistent. That could let a malicious or buggy host computer read beyond intended memory boundaries, pass malformed data deeper into the firmware, or in some cases crash the device. The patch adds explicit length and bounds assertions for many USB commands and adds tests that confirm malformed packets are rejected.

This commit fixes a bug in the COLDCARD hardware wallet firmware that prevented signing of 1-of-1 multisignature transactions. The change also hardens how the wallet detects single-key P2SH-wrapped SegWit inputs so it no longer misclassifies them as multisig when extra unrelated key paths are present. The bug could cause legitimate transactions to fail, but the patch also reduces the chance that a malformed PSBT could trick the device into treating a simple single-key input as a multisig one.

This is a bugfix for the COLDCARD hardware wallet's NFC sharing feature. Previously, when exporting data over NFC, the device would write the tag contents fresh for each tap/scan attempt. Some phones check the tag multiple times before accepting it, so the repeated re-writes could cause the export to fail or behave inconsistently. The fix writes the NFC tag once and keeps it 'live' until the user exits, allowing repeated probes to succeed. There is no direct evidence in the commit that this is a security vulnerability; it appears to be a reliability/usability fix.

This commit upgrades the COLDCARD firmware's WIF Store feature so that individual private keys imported as WIF can sign transactions even when the PSBT file lacks the usual BIP-32 key-path metadata. It adds address/scriptPubKey auto-detection, descriptor export, and Electrum-style watch-only wallet support. The change is primarily a feature enhancement, but it touches sensitive signing paths and removes a previous safety assertion that required key paths to be at least depth 8, which slightly weakens one guardrail.

This commit updates COLDCARD's BIP-322 (Bitcoin message signing / proof-of-reserves) implementation to match the finalized BIP-322 specification. The main user-visible change is that the message to be signed must now be embedded directly in the PSBT file under a new standard field, instead of being imported separately by the user. The device verifies that the embedded message matches the on-screen message before signing. The change also adds HSM policy checks so BIP-322 signing is governed by message-signing rules, and it prevents BIP-322 PSBTs from being finalized into broadcastable transactions. There is no obvious vulnerability introduced; it is primarily a standards-compliance and safety hardening patch.

This commit removes one line of code that was adding a secret value to an internal tracking list called 'spots' inside the COLDCARD firmware's sensitive-data handling. The title says it 'restores borrowed secret handling,' suggesting the previous code accidentally treated a borrowed/short-lived secret as something that needed to be tracked for later cleanup. The change is tiny and defensive, but the commit message alone does not explain whether any actual security bug resulted from the removed line.

This commit only changes test files in the COLDCARD firmware repository. It adds setup steps (like returning to the home screen before tests), updates menu navigation to match renamed menu items, and makes test assertions more flexible. There are no changes to the actual firmware or wallet code that users rely on, so this cannot directly affect device security.

This commit makes two small, unrelated tweaks to the Coldcard simulator. One adds copy-and-paste keyboard shortcuts to the simulator's terminal window. The other adds a missing 'busy_scanning' flag to the simulated QR-code scanner so it behaves more like the real hardware. Neither change affects real Coldcard devices or their security.

This commit only updates user documentation and adds a diagram showing where the NFC antenna is located on different Coldcard hardware models (Mk4, Mk5, Q1). It also updates instructions for physically disabling the NFC antenna on each model. There are no code changes and no security fix or vulnerability introduced.

This commit automates how the COLDCARD firmware records the latest Bitcoin block height during the build process. It fetches the current block height from two public Bitcoin explorer websites (mempool.space and blockstream.info) and stores it in a generated source file. That value is then used as a minimum block height for some COLDCARD security feature (likely related to 'SSSP/CCC'). The change itself is a build tooling update, not a fix for a known vulnerability, but it introduces a new external network dependency during firmware builds.

This is a tiny performance tweak in the COLDCARD wallet's menu drawing code. It changes one loop bound so the device only redraws the visible menu items instead of also iterating over off-screen items. There is no security-relevant change visible in the diff.

This commit only touches test helper code in the COLDCARD firmware repository. It fixes small test issues: allowing PSBT parsing from string input, validating a setting name in a hobble-mode test, and correctly setting sequence numbers and fallback locktimes in fake transaction generators used by multisig and general transaction tests. There is no change to the actual firmware or wallet security logic.

This commit fixes a bookkeeping bug in the COLDCARD firmware's transaction-signing logic. When two optional security features—SSSP (a spending velocity limit) and CCC (a policy that can override SSSP)—are both active, the block-height tracker for SSSP was not being updated in one specific case where CCC allowed a transaction that SSSP would have blocked. The fix ensures both trackers stay in sync, so SSSP's velocity limit remains accurate after an override. There is no direct evidence in the commit that this is exploitable as a security vulnerability; it reads as a test-driven correctness fix.

This commit only updates the project's automated test harness to work with newer versions of Bitcoin Core (specifically version 30). It changes how tests detect Bitcoin Core's version, handle removed legacy wallet features, and adjust an expected test result about data size limits. There is no change to the COLDCARD firmware itself or to any code that runs on the device, so this has no security relevance for end users.