diff --git a/pkgs/development/libraries/speex/default.nix b/pkgs/development/libraries/speex/default.nix
index a7d4aa97074..5509be7822d 100644
--- a/pkgs/development/libraries/speex/default.nix
+++ b/pkgs/development/libraries/speex/default.nix
@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurl, autoreconfHook, pkg-config, fftw, speexdsp }:
+{ lib, stdenv, fetchurl, fetchpatch, autoreconfHook, pkg-config, fftw, speexdsp }:
 
 stdenv.mkDerivation rec {
   pname = "speex";
@@ -13,6 +13,14 @@ stdenv.mkDerivation rec {
     sed -i '/AC_CONFIG_MACRO_DIR/i PKG_PROG_PKG_CONFIG' configure.ac
   '';
 
+  patches = [
+    (fetchpatch {
+      name = "CVE-2020-23903.patch";
+      url = "https://github.com/xiph/speex/commit/870ff845b32f314aec0036641ffe18aba4916887.patch";
+      sha256 = "sha256-uEMDhDTw/LIWNPPCXW6kF+udBmNO88G/jJTojAA9fs8=";
+    })
+  ];
+
   outputs = [ "out" "dev" "doc" ];
 
   nativeBuildInputs = [ autoreconfHook pkg-config ];