Australia has updated its travel advisory for Iran:

Do not travel to Iran. If you are in Iran, you should leave as soon as possible. There are violent protests across Iran that may escalate without warning. The security forces' response to the protests has been severe, and many protesters and bystanders have been injured, killed, or arrested. Avoid large public gatherings, demonstrations, and protests, and follow the advice of local authorities. Australians, including dual citizens, are at high risk of arrest. The security situation is volatile. If you remain in Iran despite our advice, you are responsible for your own safety. The Australian Embassy's operations are suspended. Our ability to provide consular assistance in Iran is extremely limited.