diff --git a/pkgs/applications/networking/instant-messengers/linphone/bc-mbedtls/default.nix b/pkgs/applications/networking/instant-messengers/linphone/bc-mbedtls/default.nix
index ad08bf4996b5..9172f6a0519c 100644
--- a/pkgs/applications/networking/instant-messengers/linphone/bc-mbedtls/default.nix
+++ b/pkgs/applications/networking/instant-messengers/linphone/bc-mbedtls/default.nix
@@ -2,6 +2,7 @@
   lib,
   stdenv,
   fetchFromGitLab,
+  fetchpatch,
 
   cmake,
   ninja,
@@ -27,6 +28,17 @@ stdenv.mkDerivation {
     fetchSubmodules = true;
   };
 
+  patches = [
+    # Fix build with gcc15
+    # https://www.github.com/Mbed-TLS/mbedtls/pull/10215
+    (fetchpatch {
+      name = "linphone-mbedtls-fix-unterminated-string-initialization.patch";
+      url = "https://github.com/Mbed-TLS/mbedtls/commit/d593c54b3cbfc3c806476a725e7d82763da0da9e.patch";
+      hash = "sha256-hh2cGzL75fEqlFNhEyL2fI9qsBW2Eq43DdWFD9qLsKE=";
+      excludes = [ "ChangeLog.d/unterminated-string-initialization.txt" ];
+    })
+  ];
+
   nativeBuildInputs = [
     cmake
     ninja