From 40e3304e9e3ecf31df16dd67a24e85d049593240 Mon Sep 17 00:00:00 2001
From: Colin McDonnell <colinmcd94@gmail.com>
Date: Wed, 10 Sep 2025 21:26:21 -0700
Subject: [PATCH 1/3] Fix error message on invalid shape. Fixes #5218

---
 packages/zod/src/v4/core/schemas.ts | 2 +-
 play.ts                             | 8 ++++++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/packages/zod/src/v4/core/schemas.ts b/packages/zod/src/v4/core/schemas.ts
index b410d79ddf..8a9bfa6cf1 100644
--- a/packages/zod/src/v4/core/schemas.ts
+++ b/packages/zod/src/v4/core/schemas.ts
@@ -1763,7 +1763,7 @@ export interface $ZodObject<
 function normalizeDef(def: $ZodObjectDef) {
   const keys = Object.keys(def.shape);
   for (const k of keys) {
-    if (!def.shape[k]._zod.traits.has("$ZodType")) {
+    if (!def.shape?.[k]?._zod?.traits?.has("$ZodType")) {
       throw new Error(`Invalid element at key "${k}": expected a Zod schema`);
     }
   }
diff --git a/play.ts b/play.ts
index 4564a8e840..6aabb3481f 100644
--- a/play.ts
+++ b/play.ts
@@ -1,3 +1,7 @@
-import * as z from "zod";
+import z from "zod";
 
-z;
+z.object({
+  inner: {
+    a: z.number(),
+  },
+}).parse({ inner: { a: 1 } });

From eeb66095cda39f70badb7657fa47e145a0b8aeb7 Mon Sep 17 00:00:00 2001
From: Colin McDonnell <colinmcd94@gmail.com>
Date: Wed, 10 Sep 2025 21:39:48 -0700
Subject: [PATCH 2/3] Ignore package.jsons

---
 packages/zod/.gitignore | 1 +
 play.ts                 | 8 ++------
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/packages/zod/.gitignore b/packages/zod/.gitignore
index 2250745510..86d865467d 100644
--- a/packages/zod/.gitignore
+++ b/packages/zod/.gitignore
@@ -4,3 +4,4 @@
 **/*.d.ts
 **/*.d.mts
 **/*.d.cts
+**/package.json
diff --git a/play.ts b/play.ts
index 6aabb3481f..4564a8e840 100644
--- a/play.ts
+++ b/play.ts
@@ -1,7 +1,3 @@
-import z from "zod";
+import * as z from "zod";
 
-z.object({
-  inner: {
-    a: z.number(),
-  },
-}).parse({ inner: { a: 1 } });
+z;

From 9915c393a0c6cd880059ea2f0b65835f16cc809a Mon Sep 17 00:00:00 2001
From: Colin McDonnell <colinmcd94@gmail.com>
Date: Wed, 10 Sep 2025 21:43:31 -0700
Subject: [PATCH 3/3] Fix CIDRv6 validation false positive. Fixes #5184

---
 packages/zod/src/v4/classic/tests/string.test.ts | 2 ++
 packages/zod/src/v4/core/schemas.ts              | 7 ++++---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/packages/zod/src/v4/classic/tests/string.test.ts b/packages/zod/src/v4/classic/tests/string.test.ts
index 5e32b92560..a223b878c1 100644
--- a/packages/zod/src/v4/classic/tests/string.test.ts
+++ b/packages/zod/src/v4/classic/tests/string.test.ts
@@ -920,6 +920,8 @@ test("CIDR v6 validation", () => {
   expect(cidrV6.safeParse("not a cidr").success).toBe(false); // Invalid format
   expect(cidrV6.safeParse("192.168.0.0/24").success).toBe(false); // IPv4 CIDR in v6 validation
   expect(cidrV6.safeParse("2001:0db8:85a3::/64/whatever-after").success).toBe(false);
+  expect(cidrV6.safeParse("22d9:f4a8:6a90:f3bf:dcaa:2beb:5fba:0000/112").success).toBe(true);
+  expect(cidrV6.safeParse("22d9:f4a8:6a90:f3bf:dcaa:2beb:5fba:0000/112/268").success).toBe(false);
 });
 
 test("E.164 validation", () => {
diff --git a/packages/zod/src/v4/core/schemas.ts b/packages/zod/src/v4/core/schemas.ts
index 8a9bfa6cf1..98aa588b1a 100644
--- a/packages/zod/src/v4/core/schemas.ts
+++ b/packages/zod/src/v4/core/schemas.ts
@@ -830,10 +830,11 @@ export const $ZodCIDRv6: core.$constructor<$ZodCIDRv6> = /*@__PURE__*/ core.$con
     $ZodStringFormat.init(inst, def);
 
     inst._zod.check = (payload) => {
-      const segments = payload.value.split("/");
-      const [address, prefix] = segments;
+      const parts = payload.value.split("/");
       try {
-        if (segments.length !== 2) throw new Error();
+        if (parts.length !== 2) throw new Error();
+        const [address, prefix] = parts;
+        if (!prefix) throw new Error();
         const prefixNum = Number(prefix);
         if (`${prefixNum}` !== prefix) throw new Error();
         if (prefixNum < 0 || prefixNum > 128) throw new Error();