diff --git a/tests/unittests/CMakeLists.txt b/tests/unittests/CMakeLists.txt
index 28458d49..f85da72b 100644
--- a/tests/unittests/CMakeLists.txt
+++ b/tests/unittests/CMakeLists.txt
@@ -30,6 +30,12 @@ set(LIBSSH_THREAD_UNIT_TESTS
     torture_threads_crypto
 )
 
+set(TORTURE_UNIT_ENVIRONMENT
+    "LSAN_OPTIONS=suppressions=${libssh-tests_SOURCE_DIR}/suppressions/lsan.supp;")
+if (OPENSSL_FOUND)
+    list(APPEND TORTURE_UNIT_ENVIRONMENT OPENSSL_ENABLE_SHA1_SIGNATURES=1)
+endif (OPENSSL_FOUND)
+
 if (UNIX AND NOT WIN32)
     set(LIBSSH_UNIT_TESTS
         ${LIBSSH_UNIT_TESTS}
@@ -104,8 +110,7 @@ foreach(_UNIT_TEST ${LIBSSH_UNIT_TESTS})
 
     set_property(TEST ${_UNIT_TEST}
                  PROPERTY
-                     ENVIRONMENT
-                        LSAN_OPTIONS=suppressions=${libssh-tests_SOURCE_DIR}/suppressions/lsan.supp;OPENSSL_ENABLE_SHA1_SIGNATURES=1)
+                     ENVIRONMENT ${TORTURE_UNIT_ENVIRONMENT})
 endforeach()
 
 if (CMAKE_USE_PTHREADS_INIT)
@@ -118,8 +123,7 @@ if (CMAKE_USE_PTHREADS_INIT)
 
     set_property(TEST ${_UNIT_TEST}
                  PROPERTY
-                    ENVIRONMENT
-                        LSAN_OPTIONS=suppressions=${libssh-tests_SOURCE_DIR}/suppressions/lsan.supp;OPENSSL_ENABLE_SHA1_SIGNATURES=1)
+                    ENVIRONMENT ${TORTURE_UNIT_ENVIRONMENT})
     endforeach()
 endif ()