Vulnerability in Shadow Project

CVE-2018-7169

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.

EPSS: 0.016 (72.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

  • cve@mitre.org (Exploit, Third Party Advisory, x_refsource_MISC, Issue Tracking)
  • cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)

Frequently asked questions

What is CVE-2018-7169?
CVE-2018-7169 is a medium-severity vulnerability in Shadow Project, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 5.3/10. Published 2018-02-15.
How severe is CVE-2018-7169?
Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2018-7169 known to be exploited?
7 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.