The vulnerability in uutils coreutils ln utility arises from improper handling of Unicode encoding (CWE-176). When using the target-directory form of ln, the program rejects source paths with non-UTF-8 filename bytes due to a logic error enforcing UTF-8 encoding. This contrasts with GNU ln's approach of treating filenames as raw bytes, which allows linking non-UTF-8 filenames correctly. The issue results in failure to stat the file and a non-zero exit code, causing local denial of service for operations involving such filenames.

This vulnerability causes the ln utility in uutils coreutils to fail when processing valid non-UTF-8 filenames, resulting in a local denial of service for scripts or system tasks relying on this utility to handle such files. There is no impact on confidentiality or integrity, only availability is affected locally.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should avoid using uutils coreutils ln utility on non-UTF-8 filenames or use GNU ln as an alternative to prevent failures.