diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5c3b6d33a..6989505f1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,7 @@ Bug Fixes:
 
 - Fix our setting of `isUserPreset` for presets, only set it to `true` if it's defined in a user presets file. [#4059](https://github.com/microsoft/vscode-cmake-tools/issues/4059)
 - Fix issue where duplicate presets are being listed in dropdown. [#4104](https://github.com/microsoft/vscode-cmake-tools/issues/4104)
+- Fix auto select active project corner case. [#4146](https://github.com/microsoft/vscode-cmake-tools/issues/4146) Contributed by STMicroelectronics
 
 ## 1.19.52
 
diff --git a/src/util.ts b/src/util.ts
index 0145a93b1..de7ce993e 100644
--- a/src/util.ts
+++ b/src/util.ts
@@ -947,7 +947,13 @@ export async function scheduleAsyncTask<T>(task: () => Promise<T>): Promise<T> {
 export function isFileInsideFolder(uri: vscode.Uri, folderPath: string): boolean {
     const parent = platformNormalizePath(folderPath);
     const file = platformNormalizePath(uri.fsPath);
-    return file.startsWith(parent);
+
+    // Ensure project path ends with a path separator to avoid partial matches
+    const parentWithEndingSeparator = parent.endsWith(path.posix.sep)
+        ? parent
+        : `${parent}${path.posix.sep}`;
+
+    return file.startsWith(parentWithEndingSeparator);
 }
 
 /**