diff --git a/.changeset/tricky-moose-travel.md b/.changeset/tricky-moose-travel.md
new file mode 100644
index 000000000000..1dcdba11dec4
--- /dev/null
+++ b/.changeset/tricky-moose-travel.md
@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+chore(deps): update dependency undici to v5.18.0
diff --git a/packages/kit/package.json b/packages/kit/package.json
index 7a43624d86d3..2c0c11784af7 100644
--- a/packages/kit/package.json
+++ b/packages/kit/package.json
@@ -22,7 +22,7 @@
 		"set-cookie-parser": "^2.5.1",
 		"sirv": "^2.0.2",
 		"tiny-glob": "^0.2.9",
-		"undici": "5.16.0"
+		"undici": "5.18.0"
 	},
 	"devDependencies": {
 		"@playwright/test": "^1.29.2",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f0be98413f85..e3015ae27950 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -283,7 +283,7 @@ importers:
       svelte-preprocess: ^5.0.0
       tiny-glob: ^0.2.9
       typescript: ^4.9.4
-      undici: 5.16.0
+      undici: 5.18.0
       uvu: ^0.5.6
       vite: ^4.0.4
     dependencies:
@@ -299,7 +299,7 @@ importers:
       set-cookie-parser: 2.5.1
       sirv: 2.0.2
       tiny-glob: 0.2.9
-      undici: 5.16.0
+      undici: 5.18.0
     devDependencies:
       '@playwright/test': 1.29.2
       '@types/connect': 3.4.35
@@ -4840,8 +4840,8 @@ packages:
       which-boxed-primitive: 1.0.2
     dev: true
 
-  /undici/5.16.0:
-    resolution: {integrity: sha512-KWBOXNv6VX+oJQhchXieUznEmnJMqgXMbs0xxH2t8q/FUAWSJvOSr/rMaZKnX5RIVq7JDn0JbP4BOnKG2SGXLQ==}
+  /undici/5.18.0:
+    resolution: {integrity: sha512-1iVwbhonhFytNdg0P4PqyIAXbdlVZVebtPDvuM36m66mRw4OGrCm2MYynJv/UENFLdP13J1nPVQzVE2zTs1OeA==}
     engines: {node: '>=12.18'}
     dependencies:
       busboy: 1.6.0