diff --git a/pkgs/by-name/ed/edk2/package.nix b/pkgs/by-name/ed/edk2/package.nix
index e986e42bd47aa..88cdcd0ce7bb0 100644
--- a/pkgs/by-name/ed/edk2/package.nix
+++ b/pkgs/by-name/ed/edk2/package.nix
@@ -41,8 +41,19 @@ edk2 = stdenv.mkDerivation {
     owner = "tianocore";
     repo = "edk2";
     rev = "edk2-stable${edk2.version}";
-    fetchSubmodules = true;
     hash = "sha256-2odaTqiAZD5xduT0dwIYWj3gY/aFPVsTFbblIsEhBiA=";
+
+    # Original submodule sources are no longer available, so the submodules are fetched manually,
+    # with unavailable sources replaced by mirrors. (https://github.com/tianocore/edk2/pull/6402)
+    fetchSubmodules = edk2.version != "202408";
+    postFetch =
+      lib.optionalString (edk2.version == "202408") lib.pipe (import ./submodules-202408.nix)
+        [
+          (lib.mapAttrsToList (
+            path: src: "cp -r -T ${fetchFromGitHub (src // { fetchSubmodules = true; })} $out/${path}"
+          ))
+          lib.concatLines
+        ];
   };
 
   src = applyPatches {
diff --git a/pkgs/by-name/ed/edk2/submodules-202408.nix b/pkgs/by-name/ed/edk2/submodules-202408.nix
new file mode 100644
index 0000000000000..e977d9afaf829
--- /dev/null
+++ b/pkgs/by-name/ed/edk2/submodules-202408.nix
@@ -0,0 +1,80 @@
+{
+  "CryptoPkg/Library/OpensslLib/openssl" = {
+    owner = "openssl";
+    repo = "openssl";
+    rev = "de90e54bbe82e5be4fb9608b6f5c308bb837d355";
+    hash = "sha256-gpnSNaqwcA9bw1FWSrQpiTwkBL9ba0C4E7aQW1ExXTI=";
+  };
+  "ArmPkg/Library/ArmSoftFloatLib/berkeley-softfloat-3" = {
+    owner = "ucb-bar";
+    repo = "berkeley-softfloat-3";
+    rev = "b64af41c3276f97f0e181920400ee056b9c88037";
+    hash = "sha256-Yflpx+mjU8mD5biClNpdmon24EHg4aWBZszbOur5VEA=";
+  };
+  "UnitTestFrameworkPkg/Library/CmockaLib/cmocka" = {
+    owner = "tianocore";
+    repo = "edk2-cmocka";
+    rev = "1cc9cde3448cdd2e000886a26acf1caac2db7cf1";
+    hash = "sha256-AEOG82bFVSl+BMYf0jdmPBiAHSUAN7XeEC9vWfkBgu8=";
+  };
+  "MdeModulePkg/Universal/RegularExpressionDxe/oniguruma" = {
+    owner = "kkos";
+    repo = "oniguruma";
+    rev = "abfc8ff81df4067f309032467785e06975678f0d";
+    hash = "sha256-rNT+d8mQM76F3i/BsLdZJUQ5IlMU1bLkeS/pRK0Y9vk=";
+  };
+  "MdeModulePkg/Library/BrotliCustomDecompressLib/brotli" = {
+    owner = "google";
+    repo = "brotli";
+    rev = "f4153a09f87cbb9c826d8fc12c74642bb2d879ea";
+    hash = "sha256-pHC3aMcJ+6//x7T/4sU32+KsstmRwbR4JZPGtdjqrMU=";
+  };
+  "BaseTools/Source/C/BrotliCompress/brotli" = {
+    owner = "google";
+    repo = "brotli";
+    rev = "f4153a09f87cbb9c826d8fc12c74642bb2d879ea";
+    hash = "sha256-pHC3aMcJ+6//x7T/4sU32+KsstmRwbR4JZPGtdjqrMU=";
+  };
+  "RedfishPkg/Library/JsonLib/jansson" = {
+    owner = "akheron";
+    repo = "jansson";
+    rev = "e9ebfa7e77a6bee77df44e096b100e7131044059";
+    hash = "sha256-41QQ3PxNnvQQmX2cLBZgAVCJVZofDb6a/i5WpsG6lHo=";
+  };
+  "UnitTestFrameworkPkg/Library/GoogleTestLib/googletest" = {
+    owner = "google";
+    repo = "googletest";
+    rev = "86add13493e5c881d7e4ba77fb91c1f57752b3a4";
+    hash = "sha256-KOGkk5PWSDpCGp85ciULPNrylAW9JNRGyeO9JCZyGq8=";
+  };
+  "UnitTestFrameworkPkg/Library/SubhookLib/subhook" = {
+    owner = "tianocore";
+    repo = "edk2-subhook";
+    rev = "83d4e1ebef3588fae48b69a7352cc21801cb70bc";
+    hash = "sha256-0X9JrYh+g39tJxVn8ofTITet9Is3Oe1avWFzdsRkM2Q=";
+  };
+  "MdePkg/Library/BaseFdtLib/libfdt" = {
+    owner = "devicetree-org";
+    repo = "pylibfdt";
+    rev = "cfff805481bdea27f900c32698171286542b8d3c";
+    hash = "sha256-BGEWqddR/iUTI+PufhYOswIU86VX9bEuMo4rjD2Zabw=";
+  };
+  "MdePkg/Library/MipiSysTLib/mipisyst" = {
+    owner = "MIPI-Alliance";
+    repo = "public-mipi-sys-t";
+    rev = "370b5944c046bab043dd8b133727b2135af7747a";
+    hash = "sha256-6wrzZNravSL/M/g792DVUa63ZWK9ydpTCnBpRBNIsHM=";
+  };
+  "CryptoPkg/Library/MbedTlsLib/mbedtls" = {
+    owner = "ARMmbed";
+    repo = "mbedtls";
+    rev = "8c89224991adff88d53cd380f42a2baa36f91454";
+    hash = "sha256-yb5migP5Tcw99XHFzJkCct4f5R6ztxPR43VQcfTGRtE=";
+  };
+  "SecurityPkg/DeviceSecurity/SpdmLib/libspdm" = {
+    owner = "DMTF";
+    repo = "libspdm";
+    rev = "50924a4c8145fc721e17208f55814d2b38766fe6";
+    hash = "sha256-GY01N0/bWdWyzDZe1b0qLlmDLz5oxpBdYug8bEs33qg=";
+  };
+}