diff --git a/packages/mimecast/changelog.yml b/packages/mimecast/changelog.yml
index b278ce1a547..ab3af9be5a0 100644
--- a/packages/mimecast/changelog.yml
+++ b/packages/mimecast/changelog.yml
@@ -1,4 +1,9 @@
 # newer versions go on top
+- version: "3.2.3"
+  changes:
+    - description: Refactored the CEL program for cloud_integrated_logs and siem_logs data streams to improve memory usage.
+      type: bugfix
+      link: https://github.com/elastic/integrations/pull/16308
 - version: "3.2.2"
   changes:
     - description: Allow setting of `batch size` in all datastreams.
diff --git a/packages/mimecast/data_stream/cloud_integrated_logs/agent/stream/cel.yml.hbs b/packages/mimecast/data_stream/cloud_integrated_logs/agent/stream/cel.yml.hbs
index c6a35419ddc..2046cec2a4c 100644
--- a/packages/mimecast/data_stream/cloud_integrated_logs/agent/stream/cel.yml.hbs
+++ b/packages/mimecast/data_stream/cloud_integrated_logs/agent/stream/cel.yml.hbs
@@ -31,6 +31,10 @@ program: |
   // If it is changed here changes should be reflected in the other data
   // streams. Do not differentiate the logic between these data streams
   // lightly; use the state variable for this unless absolutely required.
+  //
+  // Memory optimization: This program processes ONE batch file per execution
+  // cycle to avoid memory pressure. Batch URLs are stored in cursor.blobs
+  // and processed one at a time.
   state.with(
     (
       (has(state.?token.expires) && now() < timestamp(state.token.expires)) ?
@@ -73,87 +77,113 @@ program: |
       :
         work_list
       ).as(work_list,
-        get_request(
-          state.url.trim_right("/") + state.path + "?" + {
-            "type": [work_list[0].type],
-            ?"nextPage": work_list[0].?next.optMap(next, [next]),
-            ?"dateRangeStartsAt": state.?start.optMap(start, [start.format("2006-01-02")]),
-            ?"dateRangeEndsAt": state.?end.optMap(end, [end.format("2006-01-02")]),
-            ?"pageSize": state.?page_size.optMap(size, [string(int(size))]),
-          }.format_query()
-        ).with({
-          "Header": {
-            "Authorization": ["Bearer " + token.access_token],
-            "Accept": ["application/json"],
-            "Content-Type": ["application/json"],
-          }
-        }).do_request().as(resp, resp.StatusCode == 200 ?
-          bytes(resp.Body).decode_json().as(body,
-            {
-              "events": body.value.map(b, has(b.url),
-                get(b.url).as(batch, batch.StatusCode == 200 ?
-                  bytes(batch.Body).mime("application/gzip").mime("application/x-ndjson").map(e,
-                    {
-                      "message": dyn(e.encode_json()),
-                    }
-                  )
-                :
-                    [{
-                      "error": {
-                        "code": string(batch.StatusCode),
-                        "id": string(batch.Status),
-                        "message": "GET " + b.url + ": " + (
-                          size(batch.Body) != 0 ?
-                            string(batch.Body)
-                          :
-                            string(batch.Status) + ' (' + string(batch.StatusCode) + ')'
-                        ),
-                      },
-                    }]
-                )
-              ).flatten(),
-              "cursor": {
-                "work_list": (
-                  "@nextPage" in body && size(body.value) != 0 ?
-                    [work_list[0].with({"next": body["@nextPage"]})]
-                  :
-                    []
-                ) + tail(work_list),
-              },
-              "token": {
-                "access_token": token.access_token,
-                "expires": token.expires,
-              },
-              "want_more": "@nextPage" in body && size(body.value) != 0,
-            }.as(to_publish, to_publish.with({
-              "want_more": to_publish.want_more || size(to_publish.cursor.work_list) != 0,
-            }))
-          ).as(state,
-            // Check whether we still need to get more, but have
-            // no event for this type. If we do, populate events
-            // with a place-holder to be discarded by the ingest
-            // pipeline.
-            state.want_more && size(state.events) == 0 ?
-              state.with({"events": [{"message": "want_more"}]})
-            :
-              state
-          )
-        :
-          {
-            "events": {
-              "error": {
-                "code": string(resp.StatusCode),
-                "id": string(resp.Status),
-                "message": "GET " + state.path + ": " + (
-                  size(resp.Body) != 0 ?
-                    string(resp.Body)
-                  :
-                    string(resp.Status) + ' (' + string(resp.StatusCode) + ')'
+        state.?cursor.blobs.orValue([]).as(blobs,
+          // Process blobs first if any are queued, otherwise fetch batch lists.
+          (size(blobs) > 0) ?
+            // Download a single batch file.
+            get(blobs[0]).as(batch, (batch.StatusCode == 200) ?
+              {
+                "events": bytes(batch.Body).mime("application/gzip").mime("application/x-ndjson").map(e,
+                  {
+                    "message": dyn(e.encode_json()),
+                  }
                 ),
-              },
-            },
-            "want_more": false,
-          }
+                "cursor": {
+                  "blobs": tail(blobs),
+                  "work_list": work_list,
+                },
+                "token": {
+                  "access_token": token.access_token,
+                  "expires": token.expires,
+                },
+                "want_more": size(blobs) > 1 || size(work_list) != 0,
+              }
+            : (batch.StatusCode == 404) ?
+              // 404 Not Found - skip this blob and continue immediately with remaining blobs
+              {
+                "events": [{"message": "want_more"}],
+                "cursor": {
+                  "blobs": tail(blobs),
+                  "work_list": work_list,
+                },
+                "token": {
+                  "access_token": token.access_token,
+                  "expires": token.expires,
+                },
+                "want_more": size(blobs) > 1 || size(work_list) != 0,
+              }
+            :
+              // Other errors - emit error, stop processing
+              {
+                "events": {
+                  "error": {
+                    "code": string(batch.StatusCode),
+                    "id": string(batch.Status),
+                    "message": "GET " + blobs[0] + ": " + (
+                      (size(batch.Body) != 0) ?
+                        string(batch.Body)
+                      :
+                        string(batch.Status) + " (" + string(batch.StatusCode) + ")"
+                    ),
+                  },
+                },
+                "want_more": false,
+              }
+            )
+          :
+            // No blobs queued, fetch batch list from API.
+            get_request(
+              state.url.trim_right("/") + state.path + "?" + {
+                "type": [work_list[0].type],
+                ?"nextPage": work_list[0].?next.optMap(next, [next]),
+                ?"dateRangeStartsAt": state.?start.optMap(start, [start.format("2006-01-02")]),
+                ?"dateRangeEndsAt": state.?end.optMap(end, [end.format("2006-01-02")]),
+                ?"pageSize": state.?page_size.optMap(size, [string(int(size))]),
+              }.format_query()
+            ).with({
+              "Header": {
+                "Authorization": ["Bearer " + token.access_token],
+                "Accept": ["application/json"],
+                "Content-Type": ["application/json"],
+              }
+            }).do_request().as(resp, (resp.StatusCode == 200) ?
+              bytes(resp.Body).decode_json().as(body,
+                {
+                  "events": [{"message": "want_more"}],
+                  "cursor": {
+                    "blobs": body.value.map(b, b.url),
+                    "work_list": (
+                      // If there are more pages, add pagination work item.
+                      ("@nextPage" in body && size(body.value) != 0) ?
+                        [work_list[0].with({"next": body["@nextPage"]})]
+                      :
+                        []
+                    ) + tail(work_list),
+                  },
+                  "token": {
+                    "access_token": token.access_token,
+                    "expires": token.expires,
+                  },
+                  "want_more": size(body.value) != 0 || size(tail(work_list)) != 0,
+                }
+              )
+            :
+              {
+                "events": {
+                  "error": {
+                    "code": string(resp.StatusCode),
+                    "id": string(resp.Status),
+                    "message": "GET " + state.path + ": " + (
+                      (size(resp.Body) != 0) ?
+                        string(resp.Body)
+                      :
+                        string(resp.Status) + " (" + string(resp.StatusCode) + ")"
+                    ),
+                  },
+                },
+                "want_more": false,
+              }
+            )
         )
       )
     )
diff --git a/packages/mimecast/data_stream/siem_logs/agent/stream/cel.yml.hbs b/packages/mimecast/data_stream/siem_logs/agent/stream/cel.yml.hbs
index c28a8536813..16501d6343d 100644
--- a/packages/mimecast/data_stream/siem_logs/agent/stream/cel.yml.hbs
+++ b/packages/mimecast/data_stream/siem_logs/agent/stream/cel.yml.hbs
@@ -31,6 +31,10 @@ program: |
   // If it is changed here changes should be reflected in the other data
   // streams. Do not differentiate the logic between these data streams
   // lightly; use the state variable for this unless absolutely required.
+  //
+  // Memory optimization: This program processes ONE batch file per execution
+  // cycle to avoid memory pressure. Batch URLs are stored in cursor.blobs
+  // and processed one at a time.
   state.with(
     (
       (has(state.?token.expires) && now() < timestamp(state.token.expires)) ?
@@ -73,87 +77,113 @@ program: |
       :
         work_list
       ).as(work_list,
-        get_request(
-          state.url.trim_right("/") + state.path + "?" + {
-            "type": [work_list[0].type],
-            ?"nextPage": work_list[0].?next.optMap(next, [next]),
-            ?"dateRangeStartsAt": state.?start.optMap(start, [start.format("2006-01-02")]),
-            ?"dateRangeEndsAt": state.?end.optMap(end, [end.format("2006-01-02")]),
-            ?"pageSize": state.?page_size.optMap(size, [string(int(size))]),
-          }.format_query()
-        ).with({
-          "Header": {
-            "Authorization": ["Bearer " + token.access_token],
-            "Accept": ["application/json"],
-            "Content-Type": ["application/json"],
-          }
-        }).do_request().as(resp, resp.StatusCode == 200 ?
-          bytes(resp.Body).decode_json().as(body,
-            {
-              "events": body.value.map(b, has(b.url),
-                get(b.url).as(batch, batch.StatusCode == 200 ?
-                  bytes(batch.Body).mime("application/gzip").mime("application/x-ndjson").map(e,
-                    {
-                      "message": dyn(e.encode_json()),
-                    }
-                  )
-                :
-                    [{
-                      "error": {
-                        "code": string(batch.StatusCode),
-                        "id": string(batch.Status),
-                        "message": "GET " + b.url + ": " + (
-                          size(batch.Body) != 0 ?
-                            string(batch.Body)
-                          :
-                            string(batch.Status) + ' (' + string(batch.StatusCode) + ')'
-                        ),
-                      },
-                    }]
-                )
-              ).flatten(),
-              "cursor": {
-                "work_list": (
-                  "@nextPage" in body && size(body.value) != 0 ?
-                    [work_list[0].with({"next": body["@nextPage"]})]
-                  :
-                    []
-                ) + tail(work_list),
-              },
-              "token": {
-                "access_token": token.access_token,
-                "expires": token.expires,
-              },
-              "want_more": "@nextPage" in body && size(body.value) != 0,
-            }.as(to_publish, to_publish.with({
-              "want_more": to_publish.want_more || size(to_publish.cursor.work_list) != 0,
-            }))
-          ).as(state,
-            // Check whether we still need to get more, but have
-            // no event for this type. If we do, populate events
-            // with a place-holder to be discarded by the ingest
-            // pipeline.
-            state.want_more && size(state.events) == 0 ?
-              state.with({"events": [{"message": "want_more"}]})
-            :
-              state
-          )
-        :
-          {
-            "events": {
-              "error": {
-                "code": string(resp.StatusCode),
-                "id": string(resp.Status),
-                "message": "GET " + state.path + ": " + (
-                  size(resp.Body) != 0 ?
-                    string(resp.Body)
-                  :
-                    string(resp.Status) + ' (' + string(resp.StatusCode) + ')'
+        state.?cursor.blobs.orValue([]).as(blobs,
+          // Process blobs first if any are queued, otherwise fetch batch lists.
+          (size(blobs) > 0) ?
+            // Download a single batch file.
+            get(blobs[0]).as(batch, (batch.StatusCode == 200) ?
+              {
+                "events": bytes(batch.Body).mime("application/gzip").mime("application/x-ndjson").map(e,
+                  {
+                    "message": dyn(e.encode_json()),
+                  }
                 ),
-              },
-            },
-            "want_more": false,
-          }
+                "cursor": {
+                  "blobs": tail(blobs),
+                  "work_list": work_list,
+                },
+                "token": {
+                  "access_token": token.access_token,
+                  "expires": token.expires,
+                },
+                "want_more": size(blobs) > 1 || size(work_list) != 0,
+              }
+            : (batch.StatusCode == 404) ?
+              // 404 Not Found - skip this blob and continue immediately with remaining blobs
+              {
+                "events": [{"message": "want_more"}],
+                "cursor": {
+                  "blobs": tail(blobs),
+                  "work_list": work_list,
+                },
+                "token": {
+                  "access_token": token.access_token,
+                  "expires": token.expires,
+                },
+                "want_more": size(blobs) > 1 || size(work_list) != 0,
+              }
+            :
+              // Other errors - emit error, stop processing
+              {
+                "events": {
+                  "error": {
+                    "code": string(batch.StatusCode),
+                    "id": string(batch.Status),
+                    "message": "GET " + blobs[0] + ": " + (
+                      (size(batch.Body) != 0) ?
+                        string(batch.Body)
+                      :
+                        string(batch.Status) + " (" + string(batch.StatusCode) + ")"
+                    ),
+                  },
+                },
+                "want_more": false,
+              }
+            )
+          :
+            // No blobs queued, fetch batch list from API.
+            get_request(
+              state.url.trim_right("/") + state.path + "?" + {
+                "type": [work_list[0].type],
+                ?"nextPage": work_list[0].?next.optMap(next, [next]),
+                ?"dateRangeStartsAt": state.?start.optMap(start, [start.format("2006-01-02")]),
+                ?"dateRangeEndsAt": state.?end.optMap(end, [end.format("2006-01-02")]),
+                ?"pageSize": state.?page_size.optMap(size, [string(int(size))]),
+              }.format_query()
+            ).with({
+              "Header": {
+                "Authorization": ["Bearer " + token.access_token],
+                "Accept": ["application/json"],
+                "Content-Type": ["application/json"],
+              }
+            }).do_request().as(resp, (resp.StatusCode == 200) ?
+              bytes(resp.Body).decode_json().as(body,
+                {
+                  "events": [{"message": "want_more"}],
+                  "cursor": {
+                    "blobs": body.value.map(b, b.url),
+                    "work_list": (
+                      // If there are more pages, add pagination work item.
+                      ("@nextPage" in body && size(body.value) != 0) ?
+                        [work_list[0].with({"next": body["@nextPage"]})]
+                      :
+                        []
+                    ) + tail(work_list),
+                  },
+                  "token": {
+                    "access_token": token.access_token,
+                    "expires": token.expires,
+                  },
+                  "want_more": size(body.value) != 0 || size(tail(work_list)) != 0,
+                }
+              )
+            :
+              {
+                "events": {
+                  "error": {
+                    "code": string(resp.StatusCode),
+                    "id": string(resp.Status),
+                    "message": "GET " + state.path + ": " + (
+                      (size(resp.Body) != 0) ?
+                        string(resp.Body)
+                      :
+                        string(resp.Status) + " (" + string(resp.StatusCode) + ")"
+                    ),
+                  },
+                },
+                "want_more": false,
+              }
+            )
         )
       )
     )
diff --git a/packages/mimecast/manifest.yml b/packages/mimecast/manifest.yml
index 98db5f37605..58607daf707 100644
--- a/packages/mimecast/manifest.yml
+++ b/packages/mimecast/manifest.yml
@@ -1,7 +1,7 @@
 format_version: "3.3.2"
 name: mimecast
 title: "Mimecast"
-version: "3.2.2"
+version: "3.2.3"
 description: Collect logs from Mimecast with Elastic Agent.
 type: integration
 categories: ["security", "email_security"]