diff --git a/package-lock.json b/package-lock.json
index 7f42b9e6..0dd88420 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -38,7 +38,7 @@
         "prettier": "3.5.3",
         "publint": "0.3.12",
         "semantic-release": "24.2.5",
-        "sinon": "20.0.0",
+        "sinon": "21.0.0",
         "tempy": "3.1.0"
       },
       "engines": {
@@ -13949,9 +13949,9 @@
       }
     },
     "node_modules/sinon": {
-      "version": "20.0.0",
-      "resolved": "https://registry.npmjs.org/sinon/-/sinon-20.0.0.tgz",
-      "integrity": "sha512-+FXOAbdnj94AQIxH0w1v8gzNxkawVvNqE3jUzRLptR71Oykeu2RrQXXl/VQjKay+Qnh73fDt/oDfMo6xMeDQbQ==",
+      "version": "21.0.0",
+      "resolved": "https://registry.npmjs.org/sinon/-/sinon-21.0.0.tgz",
+      "integrity": "sha512-TOgRcwFPbfGtpqvZw+hyqJDvqfapr1qUlOizROIk4bBLjlsjlB00Pg6wMFXNtJRpu+eCZuVOaLatG7M8105kAw==",
       "dev": true,
       "license": "BSD-3-Clause",
       "dependencies": {
diff --git a/package.json b/package.json
index cae39d15..47eec718 100644
--- a/package.json
+++ b/package.json
@@ -51,7 +51,7 @@
     "prettier": "3.5.3",
     "publint": "0.3.12",
     "semantic-release": "24.2.5",
-    "sinon": "20.0.0",
+    "sinon": "21.0.0",
     "tempy": "3.1.0"
   },
   "engines": {