CVE-2010-1166: The fbComposite function in fbpict.c in the Render extension in the X server in X.Org X11R7.1 allows remote au

This month

HIGH 7.1DOWNGRADE

CVE-2010-1166 is a high-severity flaw (CVSS 7.1) affecting x.org. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The fbComposite function in fbpict.c in the Render extension in the X server in X.Org X11R7.1 allows remote authenticated users to cause a denial of service (memory corruption and daemon crash) or possibly execute arbitrary code via a crafted request, related to an incorrect macro definition.

Why this priority

High severity
EPSS top 7%: very likely to be exploited
Public exploit reference

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

Risk facts

CVSS score	7.1 (High)
EPSS exploit chance	5.4% (top 7%)
CISA exploited list	No
Weakness	CWE-189
Published	2010-04-29
Last modified	2026-06-16

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

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

Am I affected?

Timeline

2010-04-29 21:30 UTCPublished CVE record published
2026-06-16 23:17 UTCUpdated Record last modified

x x.org DOWNGRADE

Affected: 7.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 7.1

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 7.1 (Debian / Ubuntu)

apt-cache madison x.org sudo apt install x.org=<VERSION_BEFORE_7.1> 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_7.1> 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.

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-2010-1166?

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

Is CVE-2010-1166 being exploited?

CVE-2010-1166 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-2010-1166 affect?

CVE-2010-1166 affects x.org. Severity is high (CVSS 7.1). The fbComposite function in fbpict.c in the Render extension in the X server in X.Org X11R7.1 allows remote authenticated users to cause a denial of service (memory corruption and daemon crash) or possibly execute arbitrary code via a craft

How urgent is CVE-2010-1166?

Priority 53/100. High severity; EPSS top 7%: very likely to be exploited; Public exploit reference

Related CVEs

CVE-2010-4818 HIGH 8.5 DOWNGRADE The GLX extension in X.Org xserver 1.7.7 allows remote authenticated users to cause a denial of service (serve
CVE-2006-6103 MEDIUM 6.6 DOWNGRADE MITIGATE Integer overflow in the ProcDbeSwapBuffers function in the DBE extension for X.Org 6.8.2, 6.9.0, 7.0, and 7.1,
CVE-2006-6102 HIGH 10.0 DOWNGRADE MITIGATE Integer overflow in the ProcDbeGetVisualInfo function in the DBE extension for X.Org 6.8.2, 6.9.0, 7.0, and 7.
CVE-2006-6101 MEDIUM 6.6 DOWNGRADE MITIGATE Integer overflow in the ProcRenderAddGlyphs function in the Render extension for X.Org 6.8.2, 6.9.0, 7.0, and
CVE-2006-3740 HIGH 7.2 DOWNGRADE MITIGATE Integer overflow in the scan_cidfont function in X.Org 6.8.2 and XFree86 X server allows local users to execut

References

← Back to latest CVEs