"When curl retrieves and parses cookies from an HTTP(S) server, it accepts cookies using control codes (byte values below 32). When cookies that contain such control codes are later sent back to an HTTP(S) server, it might make the server return a 400 response. Effectively allowing a "sister site" to deny service to siblings.
We are not aware of any exploit of this flaw."
Please bump to 7.85.0.