Is it alright to massage someone with an aortic aneurysm?

Yes: With the exception of deep abdominal massage or forceful back massage when the person is lying on his stomach. In general, we advise patients with abdominal aneurysms control blood pressure, refrain from smoking, and stay away from activities that increase intraabdominal pressure (like sit-ups or crunches or heavy lifting).

It depends: The location and degree of pressure may help in determining it's effect on aneurysm. Obviously, massage far away from the aneurysm will not matter. Pressure on the aneurysm maybe a risk, especially when vigorous.