diff --git a/include/libcamera/request.h b/include/libcamera/request.h
index 4cf5ff3f7d3b..965ffa6b45b2 100644
--- a/include/libcamera/request.h
+++ b/include/libcamera/request.h
@@ -79,6 +79,8 @@ private:
 	const uint64_t cookie_;
 	Status status_;
 	bool cancelled_;
+
+	uint32_t canary_;
 };
 
 } /* namespace libcamera */
diff --git a/src/libcamera/request.cpp b/src/libcamera/request.cpp
index 7b7ef6814686..c4258480b12b 100644
--- a/src/libcamera/request.cpp
+++ b/src/libcamera/request.cpp
@@ -19,6 +19,8 @@
 #include "libcamera/internal/log.h"
 #include "libcamera/internal/tracepoints.h"
 
+#define REQUEST_CANARY 0x1F2E3D4C
+
 /**
  * \file request.h
  * \brief Describes a frame capture request to be processed by a camera
@@ -90,6 +92,8 @@ Request::Request(Camera *camera, uint64_t cookie)
 
 	LIBCAMERA_TRACEPOINT(request_construct, this);
 
+	canary_ = REQUEST_CANARY;
+
 	LOG(Request, Debug) << "Created request - cookie: " << cookie_;
 }
 
@@ -100,6 +104,8 @@ Request::~Request()
 	delete metadata_;
 	delete controls_;
 	delete validator_;
+
+	canary_ = 0;
 }
 
 /**
@@ -114,6 +120,8 @@ Request::~Request()
  */
 void Request::reuse(ReuseFlag flags)
 {
+	ASSERT(canary_ == REQUEST_CANARY);
+
 	LIBCAMERA_TRACEPOINT(request_reuse, this);
 
 	pending_.clear();
@@ -179,6 +187,8 @@ void Request::reuse(ReuseFlag flags)
  */
 int Request::addBuffer(const Stream *stream, FrameBuffer *buffer)
 {
+	ASSERT(canary_ == REQUEST_CANARY);
+
 	if (!stream) {
 		LOG(Request, Error) << "Invalid stream reference";
 		return -EINVAL;
@@ -214,6 +224,8 @@ int Request::addBuffer(const Stream *stream, FrameBuffer *buffer)
  */
 FrameBuffer *Request::findBuffer(const Stream *stream) const
 {
+	ASSERT(canary_ == REQUEST_CANARY);
+
 	const auto it = bufferMap_.find(stream);
 	if (it == bufferMap_.end())
 		return nullptr;
@@ -281,6 +293,7 @@ FrameBuffer *Request::findBuffer(const Stream *stream) const
  */
 void Request::complete()
 {
+	ASSERT(canary_ == REQUEST_CANARY);
 	ASSERT(status_ == RequestPending);
 	ASSERT(!hasPendingBuffers());
 
@@ -306,6 +319,8 @@ void Request::complete()
  */
 bool Request::completeBuffer(FrameBuffer *buffer)
 {
+	ASSERT(canary_ == REQUEST_CANARY);
+
 	LIBCAMERA_TRACEPOINT(request_complete_buffer, this, buffer);
 
 	int ret = pending_.erase(buffer);
@@ -326,6 +341,9 @@ std::string Request::toString() const
 	/* Pending, Completed, Cancelled(X). */
 	static const char *statuses = "PCX";
 
+	if (canary_ != REQUEST_CANARY)
+		return "Invalid Canary on Request";
+
 	/* Example Output: Request(55:P:1/2:6523524) */
 	ss << "Request (" << sequence_ << ":" << statuses[status_] << ":"
 	   << pending_.size() << "/" << bufferMap_.size() << ":"