The 28-year-old has played for Bayern for his entire career and is contracted until 2021, but has often been linked with a departure from Bavaria, most notably to Manchester United.
During his time at the Allianz Arena, the forward has won seven Bundesliga titles, four German Cups as well as the Champions League in 2012-13.
Muller, who is expected to be named in Joachim Low's final 23-man Germany squad for the World Cup, has now offered signs he could be swayed by a new challenge.
"Another task would certainly be interesting and attractive," he told Welt Am Sonntag.
"If the situation is different, a lot can happen.
"Basically, it is very difficult to get away from Bayern. Currently I have no thoughts to do something else."
The forward sat out Germany's 2-1 friendly defeat to Austria on Saturday but is expected to feature in their final World Cup warm-up game against Saudi Arabia on Friday in Leverkusen.
Muller's Bayern team-mate Robert Lewandowski has also been heavily tipped with a move away from Germany this summer, with the rumours intensifying after his agent Pini Zahavi told Bild that the striker wanted a "new challenge."