CVE-2026-102474 [MEDIUM] – A flaw was found in dash. The printf builtin reserves four bytes before converting a Unico

A flaw was found in dash. The printf builtin reserves four bytes before converting a Unicode u or U escape, but the multi-byte token can need five or six bytes. A local user who can supply such an escape to dash printf or echo %b, including through dash -c and a positional argument, can write one or two bytes past that reservation.