CVE-2026-93658

A TOCTOU race condition exists in the mkfifo utility of uutils coreutils. A local attacker with write access to the parent directory can swap the newly created FIFO for a symbolic link, potentially leading to privilege escalation.

A logic error in the `ln` utility of uutils coreutils causes the program to reject source paths containing non-UTF-8 filename bytes when using target-directory forms (e.g., `ln SOURCE... DIRECTORY`). While GNU ln treats filenames as raw bytes and creates links correctly, the uutils implementation enforces UTF-8 encoding.

The 'id' utility in uutils coreutils miscalculates the 'groups=' section of its output. The implementation uses the user's real GID instead of their effective GID to compute the group list, leading to potentially divergent output compared to GNU coreutils.

A vulnerability in the rm utility of uutils coreutils allows bypassing safeguards that protect the current directory. The utility correctly refuses to delete . or .., but fails to recognize equivalent paths with trailing slashes, such as ./ or .///.

The touch utility in uutils coreutils is vulnerable to a TOCTOU race condition during file creation. After identifying a missing path, the utility later attempts creation using File::create(), which internally uses O_TRUNC. An attacker can exploit this window to create a file.

A Time-of-Check to Time-of-Use (TOCTOU) race condition exists in the mv utility of uutils coreutils during cross-device operations. The utility removes the destination path before recreating it through a copy operation, which a local attacker with write access to the destination directory can exploit.

The nohup utility in uutils coreutils creates its default output file, nohup.out, without specifying explicit restricted permissions. This causes the file to inherit umask-based permissions, typically resulting in a world-readable file (0644).

A TOCTOU vulnerability in the cp utility of uutils coreutils allows an attacker to bypass the intended no-dereference behavior. The utility checks if a source path is a symbolic link using path-based metadata but subsequently opens it without the O_NOFOLLOW flag.

The 'id' utility in uutils coreutils incorrectly displays data in 'pretty print' mode when the real UID differs from the effective UID. The implementation mistakenly uses the effective GID instead of the effective UID when looking up the name of the effective user, leading to misleading output.

The cp utility in uutils coreutils is vulnerable to an information disclosure race condition. Destination files are initially created with umask-derived permissions (e.g., 0644) before being restricted to their final mode (e.g., 0600) later in the process. A local attacker can race to open the file before the permission change.