COLDCARD vulnerability what happened, and what to do
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COLDCARD mainline RNG hotfix commit ca724637

coldcard-firmware-mainline-hotfix

https://github.com/Coldcard/firmware/commit/ca72463709f4e3f8964952039d5caf955f566a87.patch

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Coinkite
Evidence role
Repository commit
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not established
Source changes
0
Detected differences
0
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Copies held
1

Immutable patch for the direct mainline source commit contained in the normal Mk4/Mk5 v5.6.0 and Q v1.5.0Q release histories.

Every check is recorded, including checks that found no text change. A detected edit is therefore bounded between two checks. The publisher's exact save time is not observable from this record. Last checked 2 Aug 2026, 00:58 UTC.

  1. Earliest copy held Current
    seen 1 Aug 2026, 06:39 UTC · Captured here text sha256 f7094a9873f7b38e7d37fd41 7,258 chars
    Extracted text as captured
    From ca72463709f4e3f8964952039d5caf955f566a87 Mon Sep 17 00:00:00 2001
    From: "Peter D. Gray" <[email protected]>
    Date: Thu, 30 Jul 2026 22:40:23 -0400
    Subject: [PATCH] fixes rng
    ---
     stm32/COLDCARD/mpconfigboard.mk     |  7 +++++++
     stm32/COLDCARD/rng.c                |  6 +++++-
     stm32/COLDCARD/rng.h                |  3 ++-
     stm32/COLDCARD_MK4/mpconfigboard.h  |  1 +
     stm32/COLDCARD_MK4/mpconfigboard.mk |  8 +++++++-
     stm32/COLDCARD_MK4/rng.c            |  6 +++++-
     stm32/COLDCARD_MK4/rng.h            |  3 ++-
     stm32/COLDCARD_Q1/mpconfigboard.mk  |  6 ++++++
     stm32/MK-Makefile                   |  2 +-
     stm32/Q1-Makefile                   |  2 +-
     stm32/shared.mk                     | 23 +++++++++++++++++++++++
     11 files changed, 60 insertions(+), 7 deletions(-)
    diff --git a/stm32/COLDCARD/mpconfigboard.mk b/stm32/COLDCARD/mpconfigboard.mk
    index fa3560f77..6d7e3cf5f 100644
    --- a/stm32/COLDCARD/mpconfigboard.mk
    +++ b/stm32/COLDCARD/mpconfigboard.mk
    @@ -69,6 +69,13 @@ COPT += -g
     # bugfix IIRC
     build-COLDCARD/boards/COLDCARD/modckcc.o: COPT = -O0 -DNDEBUG
    +# Do not compile MicroPython's fallback PRNG.  The board-specific rng.c
    +# provides rng_get(), and this empty object satisfies the upstream object list.
    +$(BUILD)/rng.o: CFLAGS += -Dpyb_rng_yasmarang=error-do-not-want-this
    +$(BUILD)/rng.o:
    +	$(ECHO) "SKIP stm32/rng.c"
    +	$(Q)$(CC) $(CFLAGS) -x c -c /dev/null -o $@
    +
     files:
     	# SRC_C: $(SRC_C)
     	@echo
    diff --git a/stm32/COLDCARD/rng.c b/stm32/COLDCARD/rng.c
    index 374cd32c6..00e3d203a 100644
    --- a/stm32/COLDCARD/rng.c
    +++ b/stm32/COLDCARD/rng.c
    @@ -79,6 +79,11 @@ static uint32_t rng_get_or_fault(void)
         return last_value;

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