diff --git a/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiDirectoryScanService.java b/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiDirectoryScanService.java
index fe475225..d381591d 100644
--- a/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiDirectoryScanService.java
+++ b/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiDirectoryScanService.java
@@ -133,6 +133,21 @@ public class WikiDirectoryScanService {
 
         for (Path file : files) {
             try {
+                // Per-file symlink guard: a symlinked file inside an allowed
+                // directory could point outside it (e.g. secret.md ->
+                // /etc/passwd). Resolve the real path and require it to stay
+                // within the validated scan root; skip escapes.
+                Path realFile;
+                try {
+                    realFile = file.toRealPath();
+                } catch (IOException e) {
+                    realFile = file.toAbsolutePath().normalize();
+                }
+                if (!realFile.startsWith(dir)) {
+                    errors.add("Skipped symlink escaping the scan root: " + file.getFileName());
+                    skipped++;
+                    continue;
+                }
                 String absolutePath = file.toAbsolutePath().normalize().toString();
                 String fileName = file.getFileName().toString();
                 String ext = getExtension(fileName);
diff --git a/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiRawMaterialService.java b/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiRawMaterialService.java
index 0f7595f5..087ff385 100644
--- a/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiRawMaterialService.java
+++ b/mateclaw-server/src/main/java/vip/mate/wiki/service/WikiRawMaterialService.java
@@ -106,7 +106,10 @@ public class WikiRawMaterialService {
         // addText dedups internally by hash, so this reuses sameContent when
         // unchanged and inserts + triggers processing when the content differs.
         WikiRawMaterialEntity raw = addText(kbId, fileName, content);
-        if (raw != null) {
+        // Only stamp the path on a genuinely new raw. When the content matched
+        // an existing raw (possibly a different file with identical content),
+        // overwriting its sourcePath would corrupt that raw's provenance.
+        if (raw != null && sameContent == null) {
             updateSourcePath(raw.getId(), absolutePath);
         }
         return sameContent == null;
diff --git a/mateclaw-server/src/test/java/vip/mate/wiki/service/WikiSourceWatcherServiceE2ETest.java b/mateclaw-server/src/test/java/vip/mate/wiki/service/WikiSourceWatcherServiceE2ETest.java
index 58dca587..86173ee0 100644
--- a/mateclaw-server/src/test/java/vip/mate/wiki/service/WikiSourceWatcherServiceE2ETest.java
+++ b/mateclaw-server/src/test/java/vip/mate/wiki/service/WikiSourceWatcherServiceE2ETest.java
@@ -33,6 +33,8 @@ class WikiSourceWatcherServiceE2ETest {
     private WikiSourceWatcherService watcherService;
     @Autowired
     private WikiKnowledgeBaseService kbService;
+    @Autowired
+    private WikiDirectoryScanService scanService;
 
     private static final java.util.concurrent.atomic.AtomicLong SEQ =
             new java.util.concurrent.atomic.AtomicLong(System.nanoTime());
@@ -64,6 +66,27 @@ class WikiSourceWatcherServiceE2ETest {
         assertEquals(1, afterEdit, "a modified file must be re-ingested");
     }
 
+    @Test
+    void symlinkFileEscapingScanRoot_isNotIngested(@TempDir Path sourceDir, @TempDir Path outside)
+            throws java.io.IOException {
+        Files.writeString(sourceDir.resolve("real.md"), "# Real\n\nlocal content");
+        Path secret = Files.writeString(outside.resolve("secret.md"), "TOP SECRET OUTSIDE");
+        Path link = sourceDir.resolve("leak.md");
+        try {
+            Files.createSymbolicLink(link, secret);
+        } catch (UnsupportedOperationException | java.io.IOException e) {
+            return; // filesystem without symlink support — skip
+        }
+
+        long kb = SEQ.incrementAndGet();
+        WikiDirectoryScanService.ScanResult result = scanService.scanDirectory(kb, sourceDir.toString());
+
+        // Only the real file is ingested; the symlink escaping the root is skipped.
+        assertEquals(1, result.added(), "symlinked file pointing outside the root must not be ingested");
+        assertTrue(result.skipped() >= 1 || !result.errors().isEmpty(),
+                "the escaping symlink should be reported as skipped");
+    }
+
     @Test
     void kbsWithoutSourceDirectory_areSkipped() {
         // A KB with no source directory must not cause errors in the cycle.