zipFix (#5762)

# Description of Changes

<!--
Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)
-->

---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### Translations (if applicable)

- [ ] I ran
[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ConvertMarkdownToPdf.java

@@ -83,7 +83,13 @@ public class ConvertMarkdownToPdf {
                     java.util.zip.ZipEntry entry;
                     while ((entry = zipIn.getNextEntry()) != null) {
                         if (!entry.isDirectory()) {
-                            java.nio.file.Path filePath = tempDirPath.resolve(entry.getName());
+                            java.nio.file.Path filePath =
+                                    tempDirPath.resolve(entry.getName()).normalize();
+                            if (!filePath.startsWith(tempDirPath)) {
+                                throw new java.io.IOException(
+                                        "ZIP entry is outside of target directory: "
+                                                + entry.getName());
+                            }
                             java.nio.file.Files.createDirectories(filePath.getParent());
                             java.nio.file.Files.copy(zipIn, filePath);
                         }