diff --git a/.github/workflows/check-arduino.yml b/.github/workflows/check-arduino.yml
index e818685..be200da 100644
--- a/.github/workflows/check-arduino.yml
+++ b/.github/workflows/check-arduino.yml
@@ -16,10 +16,10 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v7
 
       - name: Arduino Lint
-        uses: arduino/arduino-lint-action@v2
+        uses: arduino/arduino-lint-action@v3
         with:
           compliance: specification
           library-manager: update
diff --git a/.github/workflows/compile-examples.yml b/.github/workflows/compile-examples.yml
index 0dd5ac7..005d046 100644
--- a/.github/workflows/compile-examples.yml
+++ b/.github/workflows/compile-examples.yml
@@ -38,7 +38,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v7
 
       - name: Compile examples
         uses: arduino/compile-sketches@v1
@@ -56,7 +56,7 @@ jobs:
           sketches-report-path: ${{ env.SKETCHES_REPORTS_PATH }}
 
       - name: Save sketches report as workflow artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           if-no-files-found: error
           path: ${{ env.SKETCHES_REPORTS_PATH }}
diff --git a/.github/workflows/spell-check.yml b/.github/workflows/spell-check.yml
index ef7d894..8717032 100644
--- a/.github/workflows/spell-check.yml
+++ b/.github/workflows/spell-check.yml
@@ -16,7 +16,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v7
 
       - name: Spell check
         uses: codespell-project/actions-codespell@master
diff --git a/.github/workflows/sync-labels.yml b/.github/workflows/sync-labels.yml
index 53a9f54..83615bc 100644
--- a/.github/workflows/sync-labels.yml
+++ b/.github/workflows/sync-labels.yml
@@ -27,7 +27,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v7
 
       - name: Download JSON schema for labels configuration file
         id: download-schema
@@ -70,7 +70,7 @@ jobs:
           file-url: https://raw.githubusercontent.com/arduino/tooling-project-assets/main/workflow-templates/assets/sync-labels/${{ matrix.filename }}
 
       - name: Pass configuration files to next job via workflow artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           path: |
             *.yaml
@@ -105,16 +105,16 @@ jobs:
           echo "::set-output name=flag::--dry-run"
 
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v7
 
       - name: Download configuration files artifact
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: ${{ env.CONFIGURATIONS_ARTIFACT }}
           path: ${{ env.CONFIGURATIONS_FOLDER }}
 
       - name: Remove unneeded artifact
-        uses: geekyeggo/delete-artifact@v5
+        uses: geekyeggo/delete-artifact@v6
         with:
           name: ${{ env.CONFIGURATIONS_ARTIFACT }}
 
diff --git a/src/WebSocketClient.cpp b/src/WebSocketClient.cpp
index ab41b0a..443e140 100644
--- a/src/WebSocketClient.cpp
+++ b/src/WebSocketClient.cpp
@@ -167,7 +167,7 @@ size_t WebSocketClient::write(const uint8_t *aBuffer, size_t aSize)
     // check if the write size, fits in the buffer
     if ((iTxSize + aSize) > sizeof(iTxBuffer))
     {
-        aSize = sizeof(iTxSize) - iTxSize;
+        aSize = sizeof(iTxBuffer) - iTxSize;
     }
 
     // copy data into the buffer
@@ -206,25 +206,54 @@ int WebSocketClient::parseMessage()
     iRxMasked = (length & 0x80);
     length &= 0x7f;
 
-    // read the RX size
-    if (length < 126)
+    // work out how many extended length and mask bytes follow the
+    // initial opcode + length bytes
+    int extendedLength = 0;
+    if (length == 126)
     {
-        iRxSize = length;
+        extendedLength = 2;
     }
-    else if (length == 126)
+    else if (length == 127)
     {
-        iRxSize = (HttpClient::read() << 8) | HttpClient::read();
+        extendedLength = 8;
     }
-    else
+    int maskLength = iRxMasked ? (int)sizeof(iRxMaskKey) : 0;
+
+    // make sure the remaining header bytes are available before reading
+    // them, otherwise the frame header is incomplete
+    if (HttpClient::available() < (extendedLength + maskLength))
+    {
+        return 0;
+    }
+
+    // read the RX size
+    iRxSize = length;
+    if (length == 126)
+    {
+        // read each byte in a well-defined order (the evaluation order of
+        // multiple read() calls in a single expression is unspecified)
+        uint8_t b1 = HttpClient::read();
+        uint8_t b0 = HttpClient::read();
+        iRxSize = ((uint64_t)b1 << 8) | b0;
+    }
+    else if (length == 127)
     {
-        iRxSize = ((uint64_t)HttpClient::read() << 56) | 
-                    ((uint64_t)HttpClient::read() << 48) | 
-                    ((uint64_t)HttpClient::read() << 40) | 
-                    ((uint64_t)HttpClient::read() << 32) | 
-                    ((uint64_t)HttpClient::read() << 24) | 
-                    ((uint64_t)HttpClient::read() << 16) | 
-                    ((uint64_t)HttpClient::read() << 8)  |
-                    (uint64_t)HttpClient::read(); 
+        uint8_t b7 = HttpClient::read();
+        uint8_t b6 = HttpClient::read();
+        uint8_t b5 = HttpClient::read();
+        uint8_t b4 = HttpClient::read();
+        uint8_t b3 = HttpClient::read();
+        uint8_t b2 = HttpClient::read();
+        uint8_t b1 = HttpClient::read();
+        uint8_t b0 = HttpClient::read();
+        iRxSize = ((uint64_t)b7 << 56) |
+                    ((uint64_t)b6 << 48) |
+                    ((uint64_t)b5 << 40) |
+                    ((uint64_t)b4 << 32) |
+                    ((uint64_t)b3 << 24) |
+                    ((uint64_t)b2 << 16) |
+                    ((uint64_t)b1 << 8)  |
+                    (uint64_t)b0;
     }
 
     // read in the mask, if present