diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index 6c94e4dc94..be100b008c 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -78,7 +78,7 @@ jobs:
       matrix:
         build:
           - name: 'libressl heimdal'
-            install_packages: zlib1g-dev libnghttp2-dev libldap-dev heimdal-dev
+            install_packages: zlib1g-dev libidn2-dev libnghttp2-dev libldap-dev heimdal-dev
             install_steps: libressl pytest
             configure: LDFLAGS=-Wl,-rpath,/home/runner/libressl/lib --with-openssl=/home/runner/libressl --with-gssapi --enable-debug
 
@@ -103,7 +103,7 @@ jobs:
             configure: LDFLAGS=-Wl,-rpath,/home/runner/wolfssl-opensslextra/lib --with-wolfssl=/home/runner/wolfssl-opensslextra --with-wolfssh=/home/runner/wolfssh --enable-ech --enable-debug
 
           - name: 'mbedtls valgrind'
-            install_packages: libnghttp2-dev libldap-dev valgrind
+            install_packages: libnghttp2-dev libidn2-dev libldap-dev valgrind
             install_steps: mbedtls
             configure: LDFLAGS=-Wl,-rpath,/home/runner/mbedtls/lib --with-mbedtls=/home/runner/mbedtls --enable-debug
 
@@ -145,7 +145,7 @@ jobs:
             configure: LDFLAGS=-Wl,-rpath,/home/runner/awslc/lib --with-openssl=/home/runner/awslc --enable-ech
 
           - name: 'awslc'
-            install_packages: zlib1g-dev
+            install_packages: zlib1g-dev libidn2-dev
             install_steps: awslc
             generate: -DOPENSSL_ROOT_DIR=/home/runner/awslc -DUSE_ECH=ON -DCMAKE_UNITY_BUILD=OFF
 
@@ -154,7 +154,7 @@ jobs:
             configure: --with-openssl --enable-debug --disable-unity
 
           - name: 'openssl libssh2 sync-resolver valgrind'
-            install_packages: zlib1g-dev libssh2-1-dev libnghttp2-dev libldap-dev valgrind
+            install_packages: zlib1g-dev libidn2-dev libssh2-1-dev libnghttp2-dev libldap-dev valgrind
             configure: --with-openssl --enable-debug --disable-threaded-resolver --with-libssh2
 
           - name: 'openssl'