diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index 6f2f6d782648c..f5234716ed8d8 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -159,6 +159,67 @@ jobs:
           artifact-name: fpga_cw340_sival_nightly-test-results
           bucket-destination: ${{ steps.bucket_destination.outputs.BUCKET_PATH }}
 
+  fpga_cw340_slow_sival_nightly:
+    name: FPGA CW340 slow SiVal tests
+    runs-on: [ubuntu-22.04-fpga, cw340]
+
+    env:
+      GS_PATH: opentitan-test-results
+      BAZEL_TEST_RESULTS: test_results.xml
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0 # Required for the bitstream cache to work.
+          ref: ${{ inputs.branch || 'earlgrey_1.0.0' }} # Schedule only work on the default branch, but we want to run on a different branch.
+
+      - name: Install dependencies
+        uses: ./.github/actions/prepare-env
+        with:
+          service_account_json: '${{ secrets.BAZEL_CACHE_CREDS }}'
+
+      - uses: google-github-actions/setup-gcloud@v2
+
+      - name: Update hyperdebug
+        # We run the update command twice to workaround an issue with udev on the container.
+        # Where rusb cannot dynamically update its device list in CI (udev is not completely
+        # functional). If the device is in normal mode, the first thing that opentitantool
+        # does is to switch it to DFU mode and wait until it reconnects. This reconnection is
+        # never detected. But if we run the tool another time, the device list is queried again
+        # and opentitantool can finish the update. The device will now reboot in normal mode
+        # and work for the hyperdebug job.
+        run: |
+          ./bazelisk.sh run //sw/host/opentitantool -- --interface=hyperdebug_dfu transport update-firmware \
+          || ./bazelisk.sh run //sw/host/opentitantool -- --interface=hyperdebug_dfu transport update-firmware
+
+      - name: Run tests
+        if: success() || failure()
+        run: |
+          module load xilinx/vivado
+          bazel_tests="$(mktemp)"
+
+          ./bazelisk.sh query 'attr("tags", "[\[ ]cw340_sival_rom_ext[,\]]", tests(//sw/device/...))' \
+                      'intersect attr("tags", "slow_test", tests(//sw/device/...))' \
+                                                                  | grep -v examples \
+                                                                  | grep -v penetrationtests \
+                                                                  > "$bazel_tests"
+
+          ./bazelisk.sh test --build_tests_only --target_pattern_file="$bazel_tests"
+
+      - name: Compute bucket destination
+        id: bucket_destination
+        if: ${{ !cancelled() }}
+        run: |
+          BUCKET_PATH=$GS_PATH/job/${{ github.job }}/branch/${{ inputs.branch || 'earlgrey_1.0.0'}}/$(date +%Y-%m-%d-%H%M%S)_test_results.xml
+          echo "BUCKET_PATH=$BUCKET_PATH" >> $GITHUB_OUTPUT
+
+      - name: Publish Bazel test results
+        uses: ./.github/actions/publish-bazel-test-results
+        if: ${{ !cancelled() }}
+        with:
+          artifact-name: fpga_cw340_slow_sival_nightly-test-results
+          bucket-destination: ${{ steps.bucket_destination.outputs.BUCKET_PATH }}
+
   rom_e2e:
     name: ROM E2E Tests
     runs-on: [ubuntu-22.04-fpga, cw310]
diff --git a/sw/device/tests/crypto/cryptotest/cryptotest.bzl b/sw/device/tests/crypto/cryptotest/cryptotest.bzl
index 097f98c259a6c..142ff36da0913 100644
--- a/sw/device/tests/crypto/cryptotest/cryptotest.bzl
+++ b/sw/device/tests/crypto/cryptotest/cryptotest.bzl
@@ -21,6 +21,7 @@ CRYPTOTEST_EXEC_ENVS = {
     "//hw/top_earlgrey:fpga_cw310_test_rom": None,
     "//hw/top_earlgrey:fpga_cw310_sival_rom_ext": None,
     "//hw/top_earlgrey:fpga_cw340_test_rom": "fpga_cw340",
+    "//hw/top_earlgrey:fpga_cw340_sival_rom_ext": "fpga_cw340",
     "//hw/top_earlgrey:silicon_owner_sival_rom_ext": "silicon",
 }