diff --git a/scripts/sync_vendor.py b/scripts/sync_vendor.py
index 95377b29f7..c3fbbc20b3 100755
--- a/scripts/sync_vendor.py
+++ b/scripts/sync_vendor.py
@@ -16,8 +16,8 @@ vendor = {
     # "https://github.com/mackron/miniaudio/raw/refs/tags/0.11.23/miniaudio.h": "vendor/miniaudio/miniaudio.h",
     "https://github.com/mackron/miniaudio/raw/669ed3e844524fcd883231b13095baee9f6de304/miniaudio.h": "vendor/miniaudio/miniaudio.h",
 
-    "https://raw.githubusercontent.com/yhirose/cpp-httplib/refs/tags/v0.30.0/httplib.h": "vendor/cpp-httplib/httplib.h",
-    "https://raw.githubusercontent.com/yhirose/cpp-httplib/refs/tags/v0.30.0/LICENSE":   "vendor/cpp-httplib/LICENSE",
+    "https://raw.githubusercontent.com/yhirose/cpp-httplib/refs/tags/v0.30.1/httplib.h": "vendor/cpp-httplib/httplib.h",
+    "https://raw.githubusercontent.com/yhirose/cpp-httplib/refs/tags/v0.30.1/LICENSE":   "vendor/cpp-httplib/LICENSE",
 
     "https://raw.githubusercontent.com/sheredom/subprocess.h/b49c56e9fe214488493021017bf3954b91c7c1f5/subprocess.h": "vendor/sheredom/subprocess.h",
 }
diff --git a/vendor/cpp-httplib/httplib.cpp b/vendor/cpp-httplib/httplib.cpp
index a437a36ed7..d707e65fd3 100644
--- a/vendor/cpp-httplib/httplib.cpp
+++ b/vendor/cpp-httplib/httplib.cpp
@@ -1138,6 +1138,7 @@ int getaddrinfo_with_timeout(const char *node, const char *service,
 
   return ret;
 #elif TARGET_OS_MAC
+  if (!node) { return EAI_NONAME; }
   // macOS implementation using CFHost API for asynchronous DNS resolution
   CFStringRef hostname_ref = CFStringCreateWithCString(
       kCFAllocatorDefault, node, kCFStringEncodingUTF8);
@@ -5569,14 +5570,11 @@ bool Server::read_content(Stream &strm, Request &req, Response &res) {
           strm, req, res,
           // Regular
           [&](const char *buf, size_t n) {
-            // Prevent arithmetic overflow when checking sizes.
-            // Avoid computing (req.body.size() + n) directly because
-            // adding two unsigned `size_t` values can wrap around and
-            // produce a small result instead of indicating overflow.
-            // Instead, check using subtraction: ensure `n` does not
-            // exceed the remaining capacity `max_size() - size()`.
-            if (req.body.size() >= req.body.max_size() ||
-                n > req.body.max_size() - req.body.size()) {
+            // Limit decompressed body size to payload_max_length_ to protect
+            // against "zip bomb" attacks where a small compressed payload
+            // decompresses to a massive size.
+            if (req.body.size() + n > payload_max_length_ ||
+                req.body.size() + n > req.body.max_size()) {
               return false;
             }
             req.body.append(buf, n);
diff --git a/vendor/cpp-httplib/httplib.h b/vendor/cpp-httplib/httplib.h
index 43cdbc5832..613020d12c 100644
--- a/vendor/cpp-httplib/httplib.h
+++ b/vendor/cpp-httplib/httplib.h
@@ -8,8 +8,8 @@
 #ifndef CPPHTTPLIB_HTTPLIB_H
 #define CPPHTTPLIB_HTTPLIB_H
 
-#define CPPHTTPLIB_VERSION "0.30.0"
-#define CPPHTTPLIB_VERSION_NUM "0x001E00"
+#define CPPHTTPLIB_VERSION "0.30.1"
+#define CPPHTTPLIB_VERSION_NUM "0x001E01"
 
 /*
  * Platform compatibility check
@@ -205,7 +205,10 @@
 
 #pragma comment(lib, "ws2_32.lib")
 
+#ifndef _SSIZE_T_DEFINED
 using ssize_t = __int64;
+#define _SSIZE_T_DEFINED
+#endif
 #endif // _MSC_VER
 
 #ifndef S_ISREG
@@ -2443,16 +2446,20 @@ namespace detail {
 
 #if defined(_WIN32)
 inline std::wstring u8string_to_wstring(const char *s) {
-  std::wstring ws;
+  if (!s) { return std::wstring(); }
+
   auto len = static_cast<int>(strlen(s));
+  if (!len) { return std::wstring(); }
+
   auto wlen = ::MultiByteToWideChar(CP_UTF8, 0, s, len, nullptr, 0);
-  if (wlen > 0) {
-    ws.resize(wlen);
-    wlen = ::MultiByteToWideChar(
-        CP_UTF8, 0, s, len,
-        const_cast<LPWSTR>(reinterpret_cast<LPCWSTR>(ws.data())), wlen);
-    if (wlen != static_cast<int>(ws.size())) { ws.clear(); }
-  }
+  if (!wlen) { return std::wstring(); }
+
+  std::wstring ws;
+  ws.resize(wlen);
+  wlen = ::MultiByteToWideChar(
+      CP_UTF8, 0, s, len,
+      const_cast<LPWSTR>(reinterpret_cast<LPCWSTR>(ws.data())), wlen);
+  if (wlen != static_cast<int>(ws.size())) { ws.clear(); }
   return ws;
 }
 #endif