diff --git a/.github/workflows/modem__target-test.yml b/.github/workflows/modem__target-test.yml
index 02d6ed0e4..7aadb0eb2 100644
--- a/.github/workflows/modem__target-test.yml
+++ b/.github/workflows/modem__target-test.yml
@@ -15,7 +15,7 @@ jobs:
       matrix:
         idf_ver: ["latest"]
         idf_target: ["esp32c3"]
-        test: [ { app: pppd, path: test/target }, { app: sim800_c3, path: examples/pppos_client } ]
+        test: [ { app: pppd, path: test/target }, { app: sim800_c3, path: examples/pppos_client }, { app: sim800_cmux, path: examples/simple_cmux_client } ]
     runs-on: ubuntu-20.04
     container: espressif/idf:${{ matrix.idf_ver }}
     env:
@@ -54,7 +54,7 @@ jobs:
       matrix:
         idf_ver: ["latest"]
         idf_target: ["esp32c3"]
-        test: [ { app: pppd, path: test/target }, { app: sim800_c3, path: examples/pppos_client } ]
+        test: [ { app: pppd, path: test/target }, { app: sim800_c3, path: examples/pppos_client }, { app: sim800_cmux, path: examples/simple_cmux_client } ]
     needs: build_esp_modem_tests
     runs-on:
       - self-hosted
diff --git a/README.md b/README.md
index 940e8fef8..06ffba689 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 ## How to use
 
 The [ESP-Protocols](https://github.com/espressif/esp-protocols) repository contains a collection of protocol components for [ESP-IDF](https://github.com/espressif/esp-idf).
-Additionally, each component is available in [IDF Component Registry](https://components.espressif.com). 
+Additionally, each component is available in [IDF Component Registry](https://components.espressif.com).
 Please refer to instructions in [ESP-IDF](https://github.com/espressif/esp-idf)
 
 ## Components
diff --git a/components/esp_modem/.cz.yaml b/components/esp_modem/.cz.yaml
index d9ff1b8c4..ea48ef1c9 100644
--- a/components/esp_modem/.cz.yaml
+++ b/components/esp_modem/.cz.yaml
@@ -3,6 +3,6 @@ commitizen:
   bump_message: 'bump(modem): $current_version -> $new_version'
   pre_bump_hooks: python ../../ci/changelog.py esp_modem
   tag_format: modem-v$version
-  version: 1.0.2
+  version: 1.0.3
   version_files:
   - idf_component.yml
diff --git a/components/esp_modem/CHANGELOG.md b/components/esp_modem/CHANGELOG.md
index 61ffdf945..4f1655577 100644
--- a/components/esp_modem/CHANGELOG.md
+++ b/components/esp_modem/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## [1.0.3](https://github.com/espressif/esp-protocols/commits/modem-v1.0.3)
+
+### Bug Fixes
+
+- Fix to allow MSC frame (SIM800 CMUX) after v1.0.2 ([8d5947e](https://github.com/espressif/esp-protocols/commit/8d5947e), [#366](https://github.com/espressif/esp-protocols/issues/366))
+- Add CMUX example to target tests ([4f2ebaa](https://github.com/espressif/esp-protocols/commit/4f2ebaa))
+
 ## [1.0.2](https://github.com/espressif/esp-protocols/commits/modem-v1.0.2)
 
 ### Features
diff --git a/components/esp_modem/examples/simple_cmux_client/pytest_cmux.py b/components/esp_modem/examples/simple_cmux_client/pytest_cmux.py
new file mode 100644
index 000000000..208212838
--- /dev/null
+++ b/components/esp_modem/examples/simple_cmux_client/pytest_cmux.py
@@ -0,0 +1,17 @@
+# SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: Unlicense OR CC0-1.0
+from __future__ import print_function, unicode_literals
+
+
+def test_cmux_connection(dut):
+    """
+    steps:
+      1. initializes connection with SIM800
+      2. checks we get an IP
+      3. checks for the MQTT events
+    """
+    # Check the sequence of connecting, publishing, disconnecting
+    dut.expect('Modem has correctly entered multiplexed')
+    # Check for MQTT connection and the data event
+    dut.expect('TOPIC: /topic/esp-modem')
+    dut.expect('DATA: Hello modem')
diff --git a/components/esp_modem/examples/simple_cmux_client/sdkconfig.ci.sim800_cmux b/components/esp_modem/examples/simple_cmux_client/sdkconfig.ci.sim800_cmux
new file mode 100644
index 000000000..dcdb2f029
--- /dev/null
+++ b/components/esp_modem/examples/simple_cmux_client/sdkconfig.ci.sim800_cmux
@@ -0,0 +1,17 @@
+CONFIG_IDF_TARGET="esp32c3"
+# Override some defaults to enable PPP
+CONFIG_LWIP_PPP_SUPPORT=y
+CONFIG_LWIP_PPP_NOTIFY_PHASE_SUPPORT=y
+CONFIG_LWIP_PPP_PAP_SUPPORT=y
+CONFIG_LWIP_TCPIP_TASK_STACK_SIZE=4096
+CONFIG_LWIP_PPP_ENABLE_IPV6=n
+CONFIG_EXAMPLE_MODEM_UART_TX_PIN=4
+CONFIG_EXAMPLE_MODEM_UART_RX_PIN=5
+CONFIG_EXAMPLE_MODEM_DEVICE_SIM800=y
+CONFIG_EXAMPLE_MODEM_DEVICE_BG96=n
+CONFIG_EXAMPLE_MODEM_PPP_APN="lpwa.vodafone.com"
+CONFIG_ESP_SYSTEM_PANIC_PRINT_HALT=y
+CONFIG_ESP32_PANIC_PRINT_HALT=y
+CONFIG_COMPILER_CXX_EXCEPTIONS=y
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
+CONFIG_EXAMPLE_CLOSE_CMUX_AT_END=y
diff --git a/components/esp_modem/idf_component.yml b/components/esp_modem/idf_component.yml
index 0fbad8207..11e2e66e8 100644
--- a/components/esp_modem/idf_component.yml
+++ b/components/esp_modem/idf_component.yml
@@ -1,4 +1,4 @@
-version: "1.0.2"
+version: "1.0.3"
 description: esp modem
 url: https://github.com/espressif/esp-protocols/tree/master/components/esp_modem
 dependencies:
diff --git a/components/esp_modem/src/esp_modem_cmux.cpp b/components/esp_modem/src/esp_modem_cmux.cpp
index 1ce67a61f..a04c1808d 100644
--- a/components/esp_modem/src/esp_modem_cmux.cpp
+++ b/components/esp_modem/src/esp_modem_cmux.cpp
@@ -144,7 +144,7 @@ bool CMux::data_available(uint8_t *data, size_t len)
             return false;
         }
     } else if ((type & FT_UIH) == FT_UIH && dlci == 0) { // notify the internal DISC command
-        if (len > 0 && (data[0] & 0xE1) == 0xE1) {
+        if ((len > 0 && (data[0] & 0xE1) == 0xE1) || (data == nullptr)) {
             // Not a DISC, ignore (MSC frame)
             return true;
         }