Backported upstream commit https://github.com/mongodb/mongo-python-driver/commit/56b6b6dbc267d365d97c037082369dabf37405d2
Fixed CVE-2024-5629
diff -ur mongo-python-driver-3.7.0/bson/_cbsonmodule.c mongo_patch/bson/_cbsonmodule.c
--- mongo-python-driver-3.7.0/bson/_cbsonmodule.c	2018-06-26 18:08:42.000000000 +0000
+++ mongo_patch/bson/_cbsonmodule.c	2025-04-06 07:06:48.259986820 +0000
@@ -2280,6 +2280,7 @@
             uint32_t c_w_s_size;
             uint32_t code_size;
             uint32_t scope_size;
+	    uint32_t len;
             PyObject* code;
             PyObject* scope;
             PyObject* code_type;
@@ -2299,7 +2300,8 @@
             memcpy(&code_size, buffer + *position, 4);
             code_size = BSON_UINT32_FROM_LE(code_size);
             /* code_w_scope length + code length + code + scope length */
-            if (!code_size || max < code_size || max < 4 + 4 + code_size + 4) {
+	    len = 4 + 4 + code_size + 4;
+            if (!code_size || max < code_size || max < len || len < code_size) {
                 goto invalid;
             }
             *position += 4;
@@ -2322,7 +2324,8 @@
                 goto invalid;
             }
             /* code length + code + scope length + scope */
-            if ((4 + code_size + 4 + scope_size) != c_w_s_size) {
+	    len = 4 + 4 + code_size + scope_size;
+            if (scope_size < BSON_MIN_SIZE || len != c_w_s_size || len < scope_size) {
                 Py_DECREF(code);
                 goto invalid;
             }