diff --git a/cli/ssh_test.go b/cli/ssh_test.go
index ceb34cc7f6..b5e3f725f6 100644
--- a/cli/ssh_test.go
+++ b/cli/ssh_test.go
@@ -475,6 +475,10 @@ Expire-Date: 0
 		// real error from being printed.
 		t.Cleanup(cancel)
 
+		// Wait for the prompt or any output really to indicate the command has
+		// started and accepting input on stdin.
+		_ = pty.ReadRune(ctx)
+
 		pty.WriteLine("echo hello 'world'")
 		pty.ExpectMatch("hello world")
 
diff --git a/pty/ptytest/ptytest.go b/pty/ptytest/ptytest.go
index 40d7018118..6f0bae64fc 100644
--- a/pty/ptytest/ptytest.go
+++ b/pty/ptytest/ptytest.go
@@ -182,6 +182,47 @@ func (p *PTY) ExpectMatch(str string) string {
 	}
 }
 
+func (p *PTY) ReadRune(ctx context.Context) rune {
+	p.t.Helper()
+
+	// A timeout is mandatory, caller can decide by passing a context
+	// that times out.
+	if _, ok := ctx.Deadline(); !ok {
+		timeout := testutil.WaitMedium
+		p.logf("ReadRune ctx has no deadline, using %s", timeout)
+		var cancel context.CancelFunc
+		//nolint:gocritic // Rule guard doesn't detect that we're using testutil.Wait*.
+		ctx, cancel = context.WithTimeout(ctx, timeout)
+		defer cancel()
+	}
+
+	var r rune
+	match := make(chan error, 1)
+	go func() {
+		defer close(match)
+		var err error
+		r, _, err = p.runeReader.ReadRune()
+		match <- err
+	}()
+
+	select {
+	case err := <-match:
+		if err != nil {
+			p.fatalf("read error", "%v (wanted newline; got %q)", err, r)
+			return 0
+		}
+		p.logf("matched rune = %q", r)
+		return r
+	case <-ctx.Done():
+		// Ensure goroutine is cleaned up before test exit.
+		_ = p.close("read rune context done: " + ctx.Err().Error())
+		<-match
+
+		p.fatalf("read rune context done", "wanted rune; got nothing")
+		return 0
+	}
+}
+
 func (p *PTY) ReadLine() string {
 	p.t.Helper()