Is this mold? If so what can I do?

Supafly22:

Pull it out and re-caulk. Relatively cheap and simple fix.

Tacomarunner:

Looks like. Pull out that caulking and use one rated for a shower. DAP makes one, red squeeze tube. CUT remember the name exactly right now.

a-random-task:

Cut out and remove the old caulk, clean up the area and seal it back up with some new caulking.

Swish887:

Brush on peroxide.

Papamanman:

Bleach

speakeasy_slim:

Yank it and tank it bro

Symun_Ano:

Sell and get a new one

Source: Is this mold? If so what can I do?