An issue was discovered in shadow 4.5. newgidmap (in shadow-utils) is setuid and allows an unprivileged user to be placed in a user namespace where setgroups(2) is permitted. This allows an attacker to remove themselves from a supplementary group, which may allow access to certain filesystem paths if the administrator has used "group blacklisting" (e.g., chmod g-rwx) to restrict access to paths. This flaw effectively reverts a security feature in the kernel (in particular, the /proc/self/setgroups knob) to prevent this sort of privilege escalation.
History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2018-02-15T19:00:00

Updated: 2024-08-05T06:24:10.505Z

Reserved: 2018-02-15T00:00:00

Link: CVE-2018-7169

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2018-02-15T20:29:00.867

Modified: 2019-10-03T00:03:26.223

Link: CVE-2018-7169

cve-icon Redhat

Severity : Moderate

Publid Date: 2017-11-14T00:00:00Z

Links: CVE-2018-7169 - Bugzilla