diff --git a/deps/zlib/BUILD.gn b/deps/zlib/BUILD.gn
index 378bd0df75ca22..2a898d2a60cfa2 100644
--- a/deps/zlib/BUILD.gn
+++ b/deps/zlib/BUILD.gn
@@ -70,7 +70,7 @@ source_set("zlib_common_headers") {
 use_arm_neon_optimizations = false
 if ((current_cpu == "arm" || current_cpu == "arm64") &&
     !(is_win && !is_clang)) {
-  # TODO(richard.townsend@arm.com): Optimizations temporarily disabled for
+  # TODO(ritownsend@google.com): Optimizations temporarily disabled for
   # Windows on Arm MSVC builds, see http://crbug.com/v8/10012.
   if (arm_use_neon) {
     use_arm_neon_optimizations = true
diff --git a/deps/zlib/deflate.c b/deps/zlib/deflate.c
index 8a5281c2b6cd8d..49496bb3b05618 100644
--- a/deps/zlib/deflate.c
+++ b/deps/zlib/deflate.c
@@ -485,14 +485,7 @@ int ZEXPORT deflateInit2_(z_streamp strm, int level, int method,
     s->window = (Bytef *) ZALLOC(strm,
                                  s->w_size + WINDOW_PADDING,
                                  2*sizeof(Byte));
-    /* Avoid use of unitialized values in the window, see crbug.com/1137613 and
-     * crbug.com/1144420 */
-    zmemzero(s->window, (s->w_size + WINDOW_PADDING) * (2 * sizeof(Byte)));
     s->prev   = (Posf *)  ZALLOC(strm, s->w_size, sizeof(Pos));
-    /* Avoid use of uninitialized value, see:
-     * https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11360
-     */
-    zmemzero(s->prev, s->w_size * sizeof(Pos));
     s->head   = (Posf *)  ZALLOC(strm, s->hash_size, sizeof(Pos));
 
     s->high_water = 0;      /* nothing written to s->window yet */
@@ -551,6 +544,13 @@ int ZEXPORT deflateInit2_(z_streamp strm, int level, int method,
         deflateEnd (strm);
         return Z_MEM_ERROR;
     }
+    /* Avoid use of unitialized values in the window, see crbug.com/1137613 and
+     * crbug.com/1144420 */
+    zmemzero(s->window, (s->w_size + WINDOW_PADDING) * (2 * sizeof(Byte)));
+    /* Avoid use of uninitialized value, see:
+     * https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11360
+     */
+    zmemzero(s->prev, s->w_size * sizeof(Pos));
 #ifdef LIT_MEM
     s->d_buf = (ushf *)(s->pending_buf + (s->lit_bufsize << 1));
     s->l_buf = s->pending_buf + (s->lit_bufsize << 2);
diff --git a/deps/zlib/patches/0017-deflate-move-zmemzero-after-null-check.patch b/deps/zlib/patches/0017-deflate-move-zmemzero-after-null-check.patch
new file mode 100644
index 00000000000000..ac8ade53621ae0
--- /dev/null
+++ b/deps/zlib/patches/0017-deflate-move-zmemzero-after-null-check.patch
@@ -0,0 +1,49 @@
+From 93f86001b67609106c658fe0908a9b7931245b8a Mon Sep 17 00:00:00 2001
+From: pedro martelletto <martelletto@google.com>
+Date: Thu, 3 Apr 2025 16:46:42 +0000
+Subject: [PATCH] [zlib] Deflate: move zmemzero after NULL check
+
+ZALLOC() might fail, in which case dereferencing the returned pointer
+results in undefined behaviour. N.B. These conditions are not reachable
+from Chromium, as Chromium will abort rather than return nullptr from
+malloc. Found by libfido2's fuzz harness.
+---
+ third_party/zlib/deflate.c | 14 +++++++-------
+ 1 file changed, 7 insertions(+), 7 deletions(-)
+
+diff --git a/third_party/zlib/deflate.c b/third_party/zlib/deflate.c
+index 8a5281c2b6cd8..49496bb3b0561 100644
+--- a/third_party/zlib/deflate.c
++++ b/third_party/zlib/deflate.c
+@@ -485,14 +485,7 @@ int ZEXPORT deflateInit2_(z_streamp strm, int level, int method,
+     s->window = (Bytef *) ZALLOC(strm,
+                                  s->w_size + WINDOW_PADDING,
+                                  2*sizeof(Byte));
+-    /* Avoid use of unitialized values in the window, see crbug.com/1137613 and
+-     * crbug.com/1144420 */
+-    zmemzero(s->window, (s->w_size + WINDOW_PADDING) * (2 * sizeof(Byte)));
+     s->prev   = (Posf *)  ZALLOC(strm, s->w_size, sizeof(Pos));
+-    /* Avoid use of uninitialized value, see:
+-     * https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11360
+-     */
+-    zmemzero(s->prev, s->w_size * sizeof(Pos));
+     s->head   = (Posf *)  ZALLOC(strm, s->hash_size, sizeof(Pos));
+ 
+     s->high_water = 0;      /* nothing written to s->window yet */
+@@ -551,6 +544,13 @@ int ZEXPORT deflateInit2_(z_streamp strm, int level, int method,
+         deflateEnd (strm);
+         return Z_MEM_ERROR;
+     }
++    /* Avoid use of unitialized values in the window, see crbug.com/1137613 and
++     * crbug.com/1144420 */
++    zmemzero(s->window, (s->w_size + WINDOW_PADDING) * (2 * sizeof(Byte)));
++    /* Avoid use of uninitialized value, see:
++     * https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11360
++     */
++    zmemzero(s->prev, s->w_size * sizeof(Pos));
+ #ifdef LIT_MEM
+     s->d_buf = (ushf *)(s->pending_buf + (s->lit_bufsize << 1));
+     s->l_buf = s->pending_buf + (s->lit_bufsize << 2);
+-- 
+2.49.0.504.g3bcea36a83-goog
+
diff --git a/src/zlib_version.h b/src/zlib_version.h
index adbfb15d6c66f9..7d0fae9137f694 100644
--- a/src/zlib_version.h
+++ b/src/zlib_version.h
@@ -2,5 +2,5 @@
 // Refer to tools/dep_updaters/update-zlib.sh
 #ifndef SRC_ZLIB_VERSION_H_
 #define SRC_ZLIB_VERSION_H_
-#define ZLIB_VERSION "1.3.0.1-motley-788cb3c"
+#define ZLIB_VERSION "1.3.0.1-motley-780819f"
 #endif  // SRC_ZLIB_VERSION_H_