Beseiged applies to one planet at a time.
http://www.skyscript.co.uk/gl/beseiged.html
Bonatus describes a besieged planet as
one that separates from a malefic and applies to another (Con. 6). It shows a situation that is going from bad to worse.
William Lilly described a planet besieged as
one that lies between the bodies of the two malefics Mars and Saturn. His example is Mars at 10 ° Aries, Venus 13° Aries, and Saturn 15° Aries. It is generally accepted that besiegement can occur by aspect as well as bodily conjunction. As a principle it refers to a planet trapped by hostile forces on either side.
In the case of this chart, neither of the criteria hold for Venus. Venus separates from Mars but applies to Sun, not Saturn.
Venus also lies between Mars and Sun, not Mars and Saturn.
So I would say Venus is not beseiged.
If you follow the same thinking, Sun is not besieged either.