diff --git a/packages/actions/package.json b/packages/actions/package.json
index 8b29657af..2b0dedf2e 100644
--- a/packages/actions/package.json
+++ b/packages/actions/package.json
@@ -49,7 +49,7 @@
 		"meilisearch": "^0.38.0",
 		"p-limit": "^6.1.0",
 		"tslib": "^2.6.3",
-		"undici": "6.19.8"
+		"undici": "6.21.1"
 	},
 	"devDependencies": {
 		"@types/node": "^18.19.45",
diff --git a/packages/discord.js/package.json b/packages/discord.js/package.json
index 03b7f6647..ad649ffef 100644
--- a/packages/discord.js/package.json
+++ b/packages/discord.js/package.json
@@ -76,7 +76,7 @@
     "fast-deep-equal": "3.1.3",
     "lodash.snakecase": "4.1.1",
     "tslib": "^2.6.3",
-    "undici": "6.19.8"
+    "undici": "6.21.1"
   },
   "devDependencies": {
     "@discordjs/api-extractor": "workspace:^",
diff --git a/packages/proxy/package.json b/packages/proxy/package.json
index f8ddfe807..09e87eb28 100644
--- a/packages/proxy/package.json
+++ b/packages/proxy/package.json
@@ -68,7 +68,7 @@
 		"@discordjs/rest": "workspace:^",
 		"@discordjs/util": "workspace:^",
 		"tslib": "^2.6.3",
-		"undici": "6.19.8"
+		"undici": "6.21.1"
 	},
 	"devDependencies": {
 		"@discordjs/api-extractor": "workspace:^",
diff --git a/packages/rest/package.json b/packages/rest/package.json
index 3b250b2f0..1ce7624b2 100644
--- a/packages/rest/package.json
+++ b/packages/rest/package.json
@@ -91,7 +91,7 @@
 		"discord-api-types": "^0.37.119",
 		"magic-bytes.js": "^1.10.0",
 		"tslib": "^2.6.3",
-		"undici": "6.19.8"
+		"undici": "6.21.1"
 	},
 	"devDependencies": {
 		"@discordjs/api-extractor": "workspace:^",
diff --git a/packages/scripts/package.json b/packages/scripts/package.json
index effaad93d..6143c3405 100644
--- a/packages/scripts/package.json
+++ b/packages/scripts/package.json
@@ -68,7 +68,7 @@
 		"@vercel/postgres": "^0.9.0",
 		"commander": "^12.1.0",
 		"tslib": "^2.6.3",
-		"undici": "6.19.8",
+		"undici": "6.21.1",
 		"yaml": "^2.5.0"
 	},
 	"devDependencies": {
diff --git a/packages/ws/package.json b/packages/ws/package.json
index d1e680c2a..5a7502a3c 100644
--- a/packages/ws/package.json
+++ b/packages/ws/package.json
@@ -100,7 +100,7 @@
 		"tsup": "^8.2.4",
 		"turbo": "^2.0.14",
 		"typescript": "~5.5.4",
-		"undici": "6.19.8",
+		"undici": "6.21.1",
 		"vitest": "^2.0.5",
 		"zlib-sync": "^0.1.9"
 	},
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 5e72e5259..60a74e479 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -408,8 +408,8 @@ importers:
         specifier: ^2.6.3
         version: 2.6.3
       undici:
-        specifier: 6.19.8
-        version: 6.19.8
+        specifier: 6.21.1
+        version: 6.21.1
     devDependencies:
       '@types/node':
         specifier: ^18.19.45
@@ -953,8 +953,8 @@ importers:
         specifier: ^2.6.3
         version: 2.6.3
       undici:
-        specifier: 6.19.8
-        version: 6.19.8
+        specifier: 6.21.1
+        version: 6.21.1
     devDependencies:
       '@discordjs/api-extractor':
         specifier: workspace:^
@@ -1194,8 +1194,8 @@ importers:
         specifier: ^2.6.3
         version: 2.6.3
       undici:
-        specifier: 6.19.8
-        version: 6.19.8
+        specifier: 6.21.1
+        version: 6.21.1
     devDependencies:
       '@discordjs/api-extractor':
         specifier: workspace:^
@@ -1316,8 +1316,8 @@ importers:
         specifier: ^2.6.3
         version: 2.6.3
       undici:
-        specifier: 6.19.8
-        version: 6.19.8
+        specifier: 6.21.1
+        version: 6.21.1
     devDependencies:
       '@discordjs/api-extractor':
         specifier: workspace:^
@@ -1395,8 +1395,8 @@ importers:
         specifier: ^2.6.3
         version: 2.6.3
       undici:
-        specifier: 6.19.8
-        version: 6.19.8
+        specifier: 6.21.1
+        version: 6.21.1
       yaml:
         specifier: ^2.5.0
         version: 2.5.0
@@ -1759,8 +1759,8 @@ importers:
         specifier: ~5.5.4
         version: 5.5.4
       undici:
-        specifier: 6.19.8
-        version: 6.19.8
+        specifier: 6.21.1
+        version: 6.21.1
       vitest:
         specifier: ^2.0.5
         version: 2.0.5(@edge-runtime/vm@3.2.0)(@types/node@18.19.45)(happy-dom@14.12.3)(terser@5.31.6)
@@ -13079,6 +13079,10 @@ packages:
     resolution: {integrity: sha512-U8uCCl2x9TK3WANvmBavymRzxbfFYG+tAu+fgx3zxQy3qdagQqBLwJVrdyO1TBfUXvfKveMKJZhpvUYoOjM+4g==}
     engines: {node: '>=18.17'}
 
+  undici@6.21.1:
+    resolution: {integrity: sha512-q/1rj5D0/zayJB2FraXdaWxbhWiNKDvu8naDT2dl1yTlvJp4BLtOcp2a5BvgGNQpYYJzau7tf1WgKv3b+7mqpQ==}
+    engines: {node: '>=18.17'}
+
   unicode-canonical-property-names-ecmascript@2.0.0:
     resolution: {integrity: sha512-yY5PpDlfVIU5+y/BSCxAJRBIS1Zc2dDG3Ujq+sR0U+JjUevW2JhocOF+soROYDSaAezOzOKuyyixhD6mBknSmQ==}
     engines: {node: '>=4'}
@@ -28823,6 +28827,8 @@ snapshots:
 
   undici@6.19.8: {}
 
+  undici@6.21.1: {}
+
   unicode-canonical-property-names-ecmascript@2.0.0: {}
 
   unicode-match-property-ecmascript@2.0.0: