chore(deps): update module github.com/moby/sys/user to v0.4.1 [security]

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
github.com/moby/sys/user	v0.4.0 → v0.4.1

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github.com/moby/sys/user has a possible DoS via unbounded parsing of user and group database files

CVE-2026-61801 / GHSA-mjcv-p78q-w5fw

More information

Details

A denial-of-service (DoS) vulnerability exists in github.com/moby/sys/user before v0.4.1 when parsing specially crafted user or group database files. An attacker able to supply a malicious /etc/passwd or /etc/group-style file may cause excessive memory consumption, potentially resulting in process termination due to Out Of Memory (OOM) conditions.

This issue is related to containerd [CVE-2026-47262] / GHSA-jpcc-p29g-p8mq, which describes one practical exploitation path through processing untrusted container image content. Applications using github.com/moby/sys/user to parse untrusted user or group database files may be similarly affected.

Impact

github.com/moby/sys/user versions before v0.4.1 do not place sufficient limits on entries while parsing user and group database files. A specially crafted file may cause excessive memory consumption, potentially leading to process termination due to Out Of Memory (OOM) conditions.

Applications that use github.com/moby/sys/user to parse user-supplied or otherwise untrusted /etc/passwd or /etc/group files may be affected. The severity depends on whether an attacker can influence the contents of files being parsed.

Patches

This issue is fixed in github.com/moby/sys/user v0.4.1. Users should upgrade to v0.4.1 or later.

Workarounds

Avoid parsing attacker-controlled /etc/passwd or /etc/group-style files with affected versions of github.com/moby/sys/user.

Applications that must process untrusted user or group database files should validate and limit accepted input before parsing. Upgrading to v0.4.1 or later is the recommended remediation.

References

• containerd CVE-2026-47262 / GHSA-jpcc-p29g-p8mq: GHSA-jpcc-p29g-p8mq
• Fix in github.com/moby/sys/user: https://github.com/moby/sys/user/commit/210d32ba2bcb4544ee968c7f31249fe59796e60b

Severity

• CVSS Score: 5.5 / 10 (Medium)
• Vector String: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

• https://github.com/moby/sys/security/advisories/GHSA-mjcv-p78q-w5fw
• https://github.com/moby/sys/pull/221
• https://github.com/moby/sys/commit/85a71bbe1faa36c552a960e6a5f3d0cfb632fbbe
• https://github.com/advisories/GHSA-mjcv-p78q-w5fw

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Release Notes

moby/sys (github.com/moby/sys/user)

v0.4.1

What's Changed

• user: prevent possible DoS via unbounded parsing of user and group database files in CVE-2026-61801 / GHSA-mjcv-p78q-w5fw. This fixes a similar issue as CVE-2026-47262 in containerd.
• user: prevent falling back to looking up numeric usernames and improve handling of numeric user/group to prevent looking up numeric values as usernames. This fixes a similar issue as CVE-2026-46680 in containerd. #​221
• user: bump Go to 1.18, modernize #​198
• user: make code a bit more DRY #​225
• user: test cleanups #​226

Full Changelog: moby/sys@user/v0.4.0...user/v0.4.1

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