diff --git a/src/main/java/org/jenkinsci/plugins/durabletask/BourneShellScript.java b/src/main/java/org/jenkinsci/plugins/durabletask/BourneShellScript.java
index 1eb947c7..2ece052b 100644
--- a/src/main/java/org/jenkinsci/plugins/durabletask/BourneShellScript.java
+++ b/src/main/java/org/jenkinsci/plugins/durabletask/BourneShellScript.java
@@ -141,6 +141,8 @@ public String getScript() {
         ShellController c = new ShellController(ws,(os == OsType.ZOS), cookieValue, jenkinsResultTxtEncoding);
         FilePath shf = c.getScriptFile(ws);
 
+        // JENKINS-70874: if a new process is forked during this call, the writeable file handle will be copied and leading to the "Text file busy" issue
+        // when executing the script.
         shf.write(script, scriptEncodingCharset);
 
         String shell = null;
@@ -229,27 +231,32 @@ private List<String> scriptLauncherCmd(ShellController c, FilePath ws, @CheckFor
         if (os == OsType.WINDOWS) { // JENKINS-40255
             scriptPath = scriptPath.replace("\\", "/"); // cygwin sh understands mixed path  (ie : "c:/jenkins/workspace/script.sh" )
         }
+        String scriptPathCopy = scriptPath + ".copy"; // copy file to protect against "Text file busy", see JENKINS-70874
         if (capturingOutput) {
-            cmdString = String.format("{ while [ -d '%s' -a \\! -f '%s' ]; do touch '%s'; sleep 3; done } & jsc=%s; %s=$jsc %s '%s' > '%s' 2> '%s'; echo $? > '%s.tmp'; mv '%s.tmp' '%s'; wait",
+            cmdString = String.format("cp '%s' '%s'; { while [ -d '%s' -a \\! -f '%s' ]; do touch '%s'; sleep 3; done } & jsc=%s; %s=$jsc %s '%s' > '%s' 2> '%s'; echo $? > '%s.tmp'; mv '%s.tmp' '%s'; wait",
+                                      scriptPath,
+                                      scriptPathCopy,
                                       controlDir,
                                       resultFile,
                                       logFile,
                                       cookieValue,
                                       cookieVariable,
                                       interpreter,
-                                      scriptPath,
+                                      scriptPathCopy,
                                       c.getOutputFile(ws),
                                       logFile,
                                       resultFile, resultFile, resultFile);
         } else {
-            cmdString = String.format("{ while [ -d '%s' -a \\! -f '%s' ]; do touch '%s'; sleep 3; done } & jsc=%s; %s=$jsc %s '%s' > '%s' 2>&1; echo $? > '%s.tmp'; mv '%s.tmp' '%s'; wait",
+            cmdString = String.format("cp '%s' '%s'; { while [ -d '%s' -a \\! -f '%s' ]; do touch '%s'; sleep 3; done } & jsc=%s; %s=$jsc %s '%s' > '%s' 2>&1; echo $? > '%s.tmp'; mv '%s.tmp' '%s'; wait",
+                                      scriptPath,
+                                      scriptPathCopy,
                                       controlDir,
                                       resultFile,
                                       logFile,
                                       cookieValue,
                                       cookieVariable,
                                       interpreter,
-                                      scriptPath,
+                                      scriptPathCopy,
                                       logFile,
                                       resultFile, resultFile, resultFile);
         }