diff --git a/src/msgbuf.h b/src/msgbuf.h
index 437b423..cf30bad 100644
--- a/src/msgbuf.h
+++ b/src/msgbuf.h
@@ -144,17 +144,23 @@
  * @param[in] ctx - pldm_msgbuf context for extractor
  *
  * @return 0 iff there are zero bytes of data that remain unread from the buffer
- * and no overflow has occurred. Otherwise, -EBADMSG.
+ * and no overflow has occurred. Otherwise, -EBADMSG if the buffer has not been
+ * completely consumed, or -EOVERFLOW if accesses were attempted beyond the
+ * bounds of the buffer.
  */
 LIBPLDM_CC_NONNULL
 LIBPLDM_CC_ALWAYS_INLINE
 LIBPLDM_CC_WARN_UNUSED_RESULT
 int pldm_msgbuf_consumed(struct pldm_msgbuf *ctx)
 {
-	if (ctx->remaining != 0) {
+	if (ctx->remaining > 0) {
 		return -EBADMSG;
 	}
 
+	if (ctx->remaining < 0) {
+		return -EOVERFLOW;
+	}
+
 	return 0;
 }
 
@@ -187,7 +193,9 @@
  * @param[in] ctx - pldm_msgbuf context
  *
  * @return 0 if all buffer access were in-bounds and completely consume the
- * underlying buffer. Otherwise, -EBADMSG.
+ * underlying buffer. Otherwise, -EBADMSG if the buffer has not been completely
+ * consumed, or -EOVERFLOW if accesses were attempted beyond the bounds of the
+ * buffer.
  */
 LIBPLDM_CC_NONNULL
 LIBPLDM_CC_ALWAYS_INLINE
diff --git a/tests/msgbuf.cpp b/tests/msgbuf.cpp
index bb64be9..14f5d73 100644
--- a/tests/msgbuf.cpp
+++ b/tests/msgbuf.cpp
@@ -516,7 +516,7 @@
     ASSERT_EQ(pldm_msgbuf_init_errno(ctx, 0, buf, sizeof(buf)), 0);
     EXPECT_EQ(pldm_msgbuf_extract_uint8(ctx, valid), 0);
     EXPECT_NE(pldm_msgbuf_extract_uint8(ctx, invalid), 0);
-    EXPECT_EQ(pldm_msgbuf_complete_consumed(ctx), -EBADMSG);
+    EXPECT_EQ(pldm_msgbuf_complete_consumed(ctx), -EOVERFLOW);
 }
 
 TEST(msgbuf, pldm_msgbuf_insert_int32_good)