The incident happened at around 10pm on Tuesday, November 24, at Stanmore Drive, Trench.
Police said the suspect was wearing trousers with "distinctive fluorescent hoops on the legs, and may have suffered burns to their hands and face as a result of the incident".
Anyone with information is asked to contact West Mercia Police on 101 quoting reference 00628_I_24112020.
People can also report information on the 'Tell Us About' section at westmercia.police.uk
Alternatively, contact Crimestoppers anonymously on 0800 555111 or at crimestoppers-uk.org