diff --git a/storage/duckdb/README.md b/storage/duckdb/README.md
index f72cd9aa0f6..a65283eb501 100644
--- a/storage/duckdb/README.md
+++ b/storage/duckdb/README.md
@@ -62,7 +62,7 @@ Tables created with `ENGINE=DuckDB` store data in DuckDB's native format. Querie
 
 ## Building
 
-The engine is built as part of the MariaDB server tree. It lives under `storage/duckdb/` and uses `ExternalProject_Add` to build DuckDB v1.5.4 from source.
+The engine is built as part of the MariaDB server tree. It lives under `storage/duckdb/` and uses `ExternalProject_Add` to build DuckDB v1.5.5 from source.
 
 Clone the branch matching your target MariaDB version. The engine is already part of the tree under `storage/duckdb/`:
 
diff --git a/storage/duckdb/cmake/duckdb.cmake b/storage/duckdb/cmake/duckdb.cmake
index 1eb9924924d..6b9e5809ffa 100644
--- a/storage/duckdb/cmake/duckdb.cmake
+++ b/storage/duckdb/cmake/duckdb.cmake
@@ -60,6 +60,14 @@ ADD_SUBMODULE(third_parties/duckdb)
 # reconciliation). Drop when the submodule is bumped to a release containing
 # the PR: the apply below will fail loudly on an already-present setval.
 SET(_DUCKDB_PATCH "${CMAKE_CURRENT_SOURCE_DIR}/patches/duckdb-pr24061-setval.diff")
+EXECUTE_PROCESS(
+  COMMAND git -C "${DUCKDB_SUBMODULE_DIR}" rev-parse HEAD
+  OUTPUT_VARIABLE _DUCKDB_SOURCE_REVISION
+  OUTPUT_STRIP_TRAILING_WHITESPACE
+  RESULT_VARIABLE _DUCKDB_GIT_RESULT)
+IF(NOT _DUCKDB_GIT_RESULT EQUAL 0)
+  MESSAGE(FATAL_ERROR "Failed to determine the DuckDB submodule revision")
+ENDIF()
 
 # Upstream sets DUCKDB_EXTENSION_JEMALLOC_LINKED via add_extension_definitions(),
 # which runs in extension/ but NOT in src/, so allocator.cpp (in duckdb_static)
@@ -90,7 +98,7 @@ ExternalProject_Add(duckdb_build
   SOURCE_DIR      "${DUCKDB_SUBMODULE_DIR}"
   BINARY_DIR      "${_DUCKDB_BUILD_DIR}"
   # Idempotent: skip when the working tree already carries the patch.
-  PATCH_COMMAND   bash -c "git apply --reverse --check '${_DUCKDB_PATCH}' 2>/dev/null || git apply --verbose '${_DUCKDB_PATCH}'"
+  PATCH_COMMAND   bash -c "test \"$(git rev-parse HEAD)\" = '${_DUCKDB_SOURCE_REVISION}' && (git apply --reverse --check '${_DUCKDB_PATCH}' 2>/dev/null || git apply --verbose '${_DUCKDB_PATCH}')"
   CMAKE_ARGS
     -DCMAKE_BUILD_TYPE=${_DUCKDB_BUILD_TYPE}
     -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
@@ -107,7 +115,7 @@ ExternalProject_Add(duckdb_build
     "-DCMAKE_CXX_FLAGS=${_DUCKDB_EXTRA_CXX_FLAGS}"
     -DENABLE_SANITIZER=${ADDRESS_SANITIZER}
     -DENABLE_UBSAN=${UB_SANITIZER}
-    -DOVERRIDE_GIT_DESCRIBE=v1.5.4-0-g0000000000
+    -DOVERRIDE_GIT_DESCRIBE=v1.5.5-0-g0000000000
   INSTALL_COMMAND  ""
   BUILD_BYPRODUCTS ${_DUCKDB_STATIC_LIBS}
   USES_TERMINAL_BUILD ON
diff --git a/storage/duckdb/docs/architecture.md b/storage/duckdb/docs/architecture.md
index b87a027b984..3b5a2709133 100644
--- a/storage/duckdb/docs/architecture.md
+++ b/storage/duckdb/docs/architecture.md
@@ -326,5 +326,5 @@ storage/duckdb/
 │   └── row_helpers.h             — byte-level row reading utilities
 │
 ├── cmake/                        — DuckDB build integration (ExternalProject_Add)
-└── third_parties/duckdb/         — upstream DuckDB submodule (v1.5.4)
+└── third_parties/duckdb/         — upstream DuckDB submodule (v1.5.5)
 ```
diff --git a/storage/duckdb/docs/mariadb-duckdb-incompatibilities.md b/storage/duckdb/docs/mariadb-duckdb-incompatibilities.md
index 512488a5b7d..636bc2e90c3 100644
--- a/storage/duckdb/docs/mariadb-duckdb-incompatibilities.md
+++ b/storage/duckdb/docs/mariadb-duckdb-incompatibilities.md
@@ -1,7 +1,7 @@
 # MariaDB - DuckDB Incompatibilities
 
 Discovered during porting the DuckDB storage engine plugin to MariaDB 12.
-DuckDB upstream version: **v1.5.4** (submodule at `third_parties/duckdb/`).
+DuckDB upstream version: **v1.5.5** (submodule at `third_parties/duckdb/`).
 
 ---