diff --git a/UNITTESTS/stubs/EmulatedSD.cpp b/UNITTESTS/stubs/EmulatedSD.cpp
new file mode 100644
index 0000000000..40337271aa
--- /dev/null
+++ b/UNITTESTS/stubs/EmulatedSD.cpp
@@ -0,0 +1,103 @@
+#include "EmulatedSD.h"
+#include <stdio.h>
+
+class EmulatedSD_Private {
+public:
+    ~EmulatedSD_Private() {
+        if (fs) {
+            fclose(fs);
+        }
+    }
+    const char *path;
+    FILE *fs;
+    bd_size_t size;
+};
+
+EmulatedSD::EmulatedSD(const char *path)
+{
+    _p = new EmulatedSD_Private;
+    _p->path = path;
+}
+
+EmulatedSD::~EmulatedSD()
+{
+    delete _p;
+}
+
+int EmulatedSD::init()
+{
+    _p->fs = fopen(_p->path, "r+");
+    if (!_p->fs) {
+        perror("fdopen():");
+        return -1;
+    }
+    if (fseek(_p->fs, 0, SEEK_END)) {
+        perror("fseek()");
+        fclose(_p->fs);
+        _p->fs = nullptr;
+        return -1;
+    }
+    _p->size = ftell(_p->fs);
+    rewind(_p->fs);
+    return 0;
+}
+
+int EmulatedSD::deinit()
+{
+    fclose(_p->fs);
+    _p->fs = nullptr;
+}
+
+int EmulatedSD::read(void *buffer, bd_addr_t addr, bd_size_t size)
+{
+    if (!_p->fs) {
+        return -1;
+    }
+    if (fseek(_p->fs, addr, SEEK_SET)) {
+        perror("fseek()");
+        return -1;
+    }
+    size_t r = fread(buffer, size, 1, _p->fs);
+    if (r < 1) {
+        perror("fread()");
+        return -1;
+    }
+    return 0;
+}
+
+int EmulatedSD::program(const void *buffer, bd_addr_t addr, bd_size_t size)
+{
+    if (!_p->fs) {
+        return -1;
+    }
+    if (fseek(_p->fs, addr, SEEK_SET)) {
+        perror("fseek()");
+        return -1;
+    }
+    size_t r = fwrite(buffer, size, 1, _p->fs);
+    if (r < 1) {
+        perror("fread()");
+        return -1;
+    }
+    return 0;
+}
+
+bd_size_t EmulatedSD::get_read_size() const
+{
+    return 512;
+}
+bd_size_t EmulatedSD::get_program_size() const
+{
+    return 512;
+}
+bd_size_t EmulatedSD::size() const
+{
+    if (!_p->fs) {
+        return -1;
+    }
+    return _p->size;
+}
+const char *EmulatedSD::get_type() const
+{
+    return "SD";
+}
diff --git a/UNITTESTS/stubs/EmulatedSD.h b/UNITTESTS/stubs/EmulatedSD.h
new file mode 100644
index 0000000000..2393ac186e
--- /dev/null
+++ b/UNITTESTS/stubs/EmulatedSD.h
@@ -0,0 +1,77 @@
+#ifndef EMULATEDSD_H
+#define EMULATEDSD_H
+
+#include "features/storage/blockdevice/BlockDevice.h"
+
+class EmulatedSD_Private;
+
+class EmulatedSD : public mbed::BlockDevice {
+public:
+    EmulatedSD(const char *path);
+    ~EmulatedSD();
+
+    /** Initialize a block device
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int init();
+
+    /** Deinitialize a block device
+     *
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int deinit();
+
+    /** Read blocks from a block device
+     *
+     *  If a failure occurs, it is not possible to determine how many bytes succeeded
+     *
+     *  @param buffer   Buffer to write blocks to
+     *  @param addr     Address of block to begin reading from
+     *  @param size     Size to read in bytes, must be a multiple of the read block size
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int read(void *buffer, bd_addr_t addr, bd_size_t size);
+
+    /** Program blocks to a block device
+     *
+     *  The blocks must have been erased prior to being programmed
+     *
+     *  If a failure occurs, it is not possible to determine how many bytes succeeded
+     *
+     *  @param buffer   Buffer of data to write to blocks
+     *  @param addr     Address of block to begin writing to
+     *  @param size     Size to write in bytes, must be a multiple of the program block size
+     *  @return         0 on success or a negative error code on failure
+     */
+    virtual int program(const void *buffer, bd_addr_t addr, bd_size_t size);
+
+    /** Get the size of a readable block
+     *
+     *  @return         Size of a readable block in bytes
+     */
+    virtual bd_size_t get_read_size() const;
+
+    /** Get the size of a programmable block
+     *
+     *  @return         Size of a programmable block in bytes
+     *  @note Must be a multiple of the read size
+     */
+    virtual bd_size_t get_program_size() const;
+
+    /** Get the total size of the underlying device
+     *
+     *  @return         Size of the underlying device in bytes
+     */
+    virtual bd_size_t size() const;
+
+    /** Get the BlockDevice class type.
+     *
+     *  @return         A string represent the BlockDevice class type.
+     */
+    virtual const char *get_type() const;
+private:
+    EmulatedSD_Private *_p;
+};
+
+#endif // EMULATEDSD_H