CVE-2018-7169: An issue was discovered in shadow 4.5

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MEDIUM 5.3REMOTEDOWNGRADE

CVE-2018-7169 is a medium-severity flaw (CVSS 5.3) affecting shadow. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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

Why this priority

Public exploit reference
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.6% (top 25%)
CISA exploited list	No
Weakness	CWE-732
Published	2018-02-15
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: shadow project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2018-02-15 20:29 UTCPublished CVE record published
2026-06-17 02:02 UTCUpdated Record last modified

shadow project shadow DOWNGRADE

Affected: 4.5

Fixed in: no fixed release known

Safe to downgrade to: a release before 4.5

1. Check installed version

apt-cache policy shadow || rpm -q shadow || shadow --version

2. No fixed release: DOWNGRADE to a release before 4.5 (Debian / Ubuntu)

apt-cache madison shadow sudo apt install shadow=<VERSION_BEFORE_4.5> sudo apt-mark hold shadow

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list shadow sudo dnf downgrade shadow-<VERSION_BEFORE_4.5> sudo dnf versionlock add shadow

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2018-7169?

shadow: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2018-7169 being exploited?

CVE-2018-7169 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2018-7169 affect?

CVE-2018-7169 affects shadow. Severity is medium (CVSS 5.3). 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

How urgent is CVE-2018-7169?

Priority 47/100. Public exploit reference; Remotely exploitable, no login, no user action

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References

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