diff --git a/extensions/mermaid-chat-features/package-lock.json b/extensions/mermaid-chat-features/package-lock.json
index 87e151df..22e704b2 100644
--- a/extensions/mermaid-chat-features/package-lock.json
+++ b/extensions/mermaid-chat-features/package-lock.json
@@ -9,7 +9,7 @@
       "version": "1.0.0",
       "license": "MIT",
       "dependencies": {
-        "dompurify": "^3.2.7",
+        "dompurify": "^3.4.1",
         "mermaid": "^11.12.2"
       },
       "devDependencies": {
@@ -1026,9 +1026,9 @@
       }
     },
     "node_modules/dompurify": {
-      "version": "3.2.7",
-      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.2.7.tgz",
-      "integrity": "sha512-WhL/YuveyGXJaerVlMYGWhvQswa7myDG17P7Vu65EWC05o8vfeNbvNf4d/BOvH99+ZW+LlQsc1GDKMa1vNK6dw==",
+      "version": "3.4.1",
+      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.4.1.tgz",
+      "integrity": "sha512-JahakDAIg1gyOm7dlgWSDjV4n7Ip2PKR55NIT6jrMfIgLFgWo81vdr1/QGqWtFNRqXP9UV71oVePtjqS2ebnPw==",
       "license": "(MPL-2.0 OR Apache-2.0)",
       "optionalDependencies": {
         "@types/trusted-types": "^2.0.7"
diff --git a/extensions/mermaid-chat-features/package.json b/extensions/mermaid-chat-features/package.json
index fafb5960..a22cf353 100644
--- a/extensions/mermaid-chat-features/package.json
+++ b/extensions/mermaid-chat-features/package.json
@@ -82,7 +82,7 @@
     "@types/node": "^22.18.10"
   },
   "dependencies": {
-    "dompurify": "^3.2.7",
+    "dompurify": "^3.4.1",
     "mermaid": "^11.12.2"
   }
 }