uncorroborated (adj.)

• apocryphal
• groundless
• inconclusive
• indecisive
• unauthentic
• uncertified
• unchecked
• unconfirmed
• undetermined
• unestablished
• unfixed
• unfounded
• unofficial
• unproved
• unproven
• unsettled
• unsubstantiated
• unsupported
• untested
• untried
• unverified
• unwarranted