CVE-2026-61801

A flaw was found in the moby/sys/user package. The package does not properly limit memory allocation when parsing Unix-style user and group database files, such as /etc/passwd or /etc/group. An attacker who can supply a specially crafted file can cause excessive memory consumption, leading to a Denial of Service (DoS) condition by crashing the affected process.

This vulnerability is rated as Moderate impact because exploitation requires supplying a malicious user or group database file to an affected tool, and the resulting impact is limited to an out-of-memory denial of service without compromising confidentiality, integrity, or elevating privileges. Across Red Hat enterprise environments, container management utilities and orchestration platforms invoke these routines when inspecting filesystem layers or resolving identity information during container execution. While an attacker capable of providing a specially crafted database file could trigger resource exhaustion and terminate the consuming process, the flaw does not facilitate container escapes or host compromise.

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.