diff --git a/changes/ce/fix-12773.en.md b/changes/ce/fix-12773.en.md
new file mode 100644
index 000000000..c4a1f80aa
--- /dev/null
+++ b/changes/ce/fix-12773.en.md
@@ -0,0 +1,8 @@
+Upgrade HTTP client libraries.
+
+The HTTP client library (`gun-1.3`) incorrectly appends a `:portnumber` suffix to the `Host` header for
+standard ports (`http` on port 80, `https` on port 443). This could cause compatibility issues with servers or
+gateways performing strict `Host` header checks (e.g., AWS Lambda, Alibaba Cloud HTTP gateways), leading to
+errors such as `InvalidCustomDomain.NotFound` or "The specified CustomDomain does not exist."
+
+
diff --git a/mix.exs b/mix.exs
index 09f5f0692..74c33f6b3 100644
--- a/mix.exs
+++ b/mix.exs
@@ -49,7 +49,7 @@ defmodule EMQXUmbrella.MixProject do
       {:redbug, github: "emqx/redbug", tag: "2.0.10"},
       {:covertool, github: "zmstone/covertool", tag: "2.0.4.1", override: true},
       {:typerefl, github: "ieQu1/typerefl", tag: "0.9.1", override: true},
-      {:ehttpc, github: "emqx/ehttpc", tag: "0.4.12", override: true},
+      {:ehttpc, github: "emqx/ehttpc", tag: "0.4.13", override: true},
       {:gproc, github: "emqx/gproc", tag: "0.9.0.1", override: true},
       {:jiffy, github: "emqx/jiffy", tag: "1.0.6", override: true},
       {:cowboy, github: "emqx/cowboy", tag: "2.9.2", override: true},
@@ -77,7 +77,7 @@ defmodule EMQXUmbrella.MixProject do
       {:esasl, github: "emqx/esasl", tag: "0.2.0"},
       {:jose, github: "potatosalad/erlang-jose", tag: "1.11.2"},
       # in conflict by ehttpc and emqtt
-      {:gun, github: "emqx/gun", tag: "1.3.10", override: true},
+      {:gun, github: "emqx/gun", tag: "1.3.11", override: true},
       # in conflict by emqx_connector and system_monitor
       {:epgsql, github: "emqx/epgsql", tag: "4.7.1.1", override: true},
       # in conflict by emqx and observer_cli
diff --git a/rebar.config b/rebar.config
index 238dca515..b4d52e867 100644
--- a/rebar.config
+++ b/rebar.config
@@ -76,8 +76,8 @@
     {covertool, {git, "https://github.com/zmstone/covertool", {tag, "2.0.4.1"}}},
     {gpb, "4.19.9"},
     {typerefl, {git, "https://github.com/ieQu1/typerefl", {tag, "0.9.1"}}},
-    {gun, {git, "https://github.com/emqx/gun", {tag, "1.3.10"}}},
-    {ehttpc, {git, "https://github.com/emqx/ehttpc", {tag, "0.4.12"}}},
+    {gun, {git, "https://github.com/emqx/gun", {tag, "1.3.11"}}},
+    {ehttpc, {git, "https://github.com/emqx/ehttpc", {tag, "0.4.13"}}},
     {gproc, {git, "https://github.com/emqx/gproc", {tag, "0.9.0.1"}}},
     {jiffy, {git, "https://github.com/emqx/jiffy", {tag, "1.0.6"}}},
     {cowboy, {git, "https://github.com/emqx/cowboy", {tag, "2.9.2"}}},