Bug 2548507

Summary: CVE-2026-61801 apptainer: moby/sys/user: Denial of Service via crafted user or group database files [epel-all]
Product: [Fedora] Fedora EPEL Reporter: Ronit Dey <rdey>
Component: apptainerAssignee: Dave Dykstra <dwd>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: epel10CC: dwd, go-sig
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["33d51d5c-d0f9-4ec6-b07d-e05ccc203c89"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-10-13 22:43:15 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2548048    

Description Ronit Dey 2026-10-09 11:37:45 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

The `github.com/moby/sys/user` package provides Go utilities for parsing and looking up entries in Unix-style user and group database files. Versions before 0.4.1 do not sufficiently limit entries when parsing `/etc/passwd`- or `/etc/group`-style files, allowing an attacker who can supply a specially crafted file to cause excessive memory consumption and potentially terminate the affected process due to an out-of-memory condition. This issue is patched in version 0.4.1. As a workaround, avoid parsing attacker-controlled user or group database files, or validate and limit untrusted input before parsing it.
Comment 1 Dave Dykstra 2026-10-13 22:43:15 UTC 
In apptainer this would only impact the user itself, so there's no security impact.  It will be included in 1.6.0 anyway.