CVE-2013-4331: Light Display Manager (aka LightDM) 1.4.x before 1.4.3, 1.6.x before 1.6.2, and 1.7.x before 1.7.14 uses 0664

Routine

LOW 2.1DOWNGRADE

CVE-2013-4331 is a low-severity flaw (CVSS 2.1) affecting lightdm. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Light Display Manager (aka LightDM) 1.4.x before 1.4.3, 1.6.x before 1.6.2, and 1.7.x before 1.7.14 uses 0664 permissions for the temporary .Xauthority file, which allows local users to obtain sensitive information by reading the file.

Why this priority

No elevated risk signals yet

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

Risk facts

CVSS score	2.1 (Low)
EPSS exploit chance	0.4% (top 69%)
CISA exploited list	No
Weakness	CWE-264
Published	2014-02-02
Last modified	2026-06-16

Publisher (CNA): Red Hat, Inc. · Vendor: robert ancell

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2014-02-02 00:55 UTCPublished CVE record published
2026-06-16 23:57 UTCUpdated Record last modified

robert ancell lightdm DOWNGRADE

Affected: 1.4.0 · 1.4.1 · 1.4.2 · 1.6.0 · 1.6.1 · 1.7.0 · 1.7.1 · 1.7.2

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.4.0

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 1.4.0 (Debian / Ubuntu)

apt-cache madison lightdm sudo apt install lightdm=<VERSION_BEFORE_1.4.0> sudo apt-mark hold lightdm

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

dnf --showduplicates list lightdm sudo dnf downgrade lightdm-<VERSION_BEFORE_1.4.0> sudo dnf versionlock add lightdm

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-2013-4331?

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

Is CVE-2013-4331 being exploited?

CVE-2013-4331 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-2013-4331 affect?

CVE-2013-4331 affects lightdm. Severity is low (CVSS 2.1). Light Display Manager (aka LightDM) 1.4.x before 1.4.3, 1.6.x before 1.6.2, and 1.7.x before 1.7.14 uses 0664 permissions for the temporary .Xauthority file, which allows local users to obtain sensitive information by reading the file.

How urgent is CVE-2013-4331?

Priority 15/100. No elevated risk signals yet.

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References

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