CVE-2026-3184

A flaw was found in util-linux. Improper hostname canonicalization in the login(1) utility, when invoked with the -h option, can modify the supplied remote hostname before setting PAM_RHOST. A remote attacker could exploit this by providing a specially crafted hostname, potentially bypassing host-based Pluggable Authentication Modules (PAM) access control rules that rely on fully qualified domain names. This could lead to unauthorized access.

This issue was rated as a Low severity issue. This is an authorization policy bypass limited to host-based access control decisions. It does not bypass authentication or grant elevated privileges. Exploitation is configuration-dependent and primarily affects legacy or uncommon remote login pathways, but it can violate administrator intent and weaken PAM-based security policy enforcement.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.