diff --git a/bucket/z3.json b/bucket/z3.json
index f45cc1998d..9c1ddabcba 100644
--- a/bucket/z3.json
+++ b/bucket/z3.json
@@ -1,18 +1,18 @@
 {
-    "version": "4.12.2",
+    "version": "4.12.3",
     "description": "Theorem prover from Microsoft Research.",
     "homepage": "https://github.com/Z3Prover/z3",
     "license": "MIT",
     "architecture": {
         "64bit": {
-            "url": "https://github.com/Z3Prover/z3/releases/download/z3-4.12.2/z3-4.12.2-x64-win.zip",
-            "hash": "ea33132e4531dbdc2c98b5f3c01257ca2f954e0f9c9115e63ea4e2530550e1d4",
-            "extract_dir": "z3-4.12.2-x64-win"
+            "url": "https://github.com/Z3Prover/z3/releases/download/z3-4.12.3/z3-4.12.3-x64-win.zip",
+            "hash": "4b728f8c167adaa6ffc5f4afd736796f0e6f9805e02c5c65e0f77e19277009c8",
+            "extract_dir": "z3-4.12.3-x64-win"
         },
         "32bit": {
-            "url": "https://github.com/Z3Prover/z3/releases/download/z3-4.12.2/z3-4.12.2-x86-win.zip",
-            "hash": "39c5f72eb7fcb4cdf6d5019fb22d13b40efc1c90cfc36c7f92adc9d1774091bd",
-            "extract_dir": "z3-4.12.2-x64-win"
+            "url": "https://github.com/Z3Prover/z3/releases/download/z3-4.12.3/z3-4.12.3-x86-win.zip",
+            "hash": "bd50b6319b9cb0848902c588456161aeffa2cf20ac1be4e9e6fe47c2b5c94fa3",
+            "extract_dir": "z3-4.12.3-x64-win"
         }
     },
     "bin": "bin\\z3.exe",