CVE-2006-6101: Integer overflow in the ProcRenderAddGlyphs function in the Render extension for X.Org 6.8.2, 6.9.0, 7.0, and

Routine

MEDIUM 6.6DOWNGRADEMITIGATE

CVE-2006-6101 is a medium-severity flaw (CVSS 6.6) affecting x.org, xfree86. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Integer overflow in the ProcRenderAddGlyphs function in the Render extension for X.Org 6.8.2, 6.9.0, 7.0, and 7.1, and XFree86 X server, allows local users to execute arbitrary code via a crafted X protocol request that triggers memory corruption during processing of glyph management data structures.

Why this priority

No elevated risk signals yet

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

Risk facts

CVSS score	6.6 (Medium)
EPSS exploit chance	0.4% (top 67%)
CISA exploited list	No
Published	2006-12-31
Last modified	2026-06-16

Publisher (CNA): Red Hat, Inc. · Vendor: x.org · xfree86 project

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

Am I affected?

Timeline

2006-12-31 05:00 UTCPublished CVE record published
2026-06-16 22:32 UTCUpdated Record last modified

x.org x.org DOWNGRADE

Affected: 6.8.2 · 6.9.0 · 7.0 · 7.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 6.8.2

1. Check installed version

apt-cache policy x.org || rpm -q x.org || x.org --version

2. No fixed release: DOWNGRADE to a release before 6.8.2 (Debian / Ubuntu)

apt-cache madison x.org sudo apt install x.org=<VERSION_BEFORE_6.8.2> sudo apt-mark hold x.org

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

dnf --showduplicates list x.org sudo dnf downgrade x.org-<VERSION_BEFORE_6.8.2> sudo dnf versionlock add x.org

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.

xfree86 project xfree86 MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy xfree86 || rpm -q xfree86 || xfree86 --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

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-2006-6101?

x.org: downgrade or apply the listed mitigation; xfree86: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2006-6101 being exploited?

CVE-2006-6101 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-2006-6101 affect?

CVE-2006-6101 affects x.org, xfree86. Severity is medium (CVSS 6.6). Integer overflow in the ProcRenderAddGlyphs function in the Render extension for X.Org 6.8.2, 6.9.0, 7.0, and 7.1, and XFree86 X server, allows local users to execute arbitrary code via a crafted X protocol request that triggers memory corr

How urgent is CVE-2006-6101?

Priority 31/100. No elevated risk signals yet.

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References

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