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CVE-2023-6816

X.org X Server buffer overflow

9.8 CRITICALEPSS 2.11%
  1. Published18 Jan 2024

Description

A flaw was found in X.Org server. Both DeviceFocusEvent and the XIQueryPointer reply contain a bit for each logical button currently down. Buttons can be arbitrarily mapped to any value up to 255, but the X.Org Server was only allocating space for the device's particular number of buttons, leading to a heap overflow if a bigger value was used.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

X.org X Server< 21.1.11
X.org Xwayland< 23.2.4
Debian Linux10.0
Fedoraproject Fedora39
Redhat Enterprise Linux Desktop7.0
Redhat Enterprise Linux Server7.0
Redhat Enterprise Linux Workstation7.0

Remediation

Fixed in
X.org X Server≥ 21.1.11
X.org Xwayland≥ 23.2.4

References

and 14 more references

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Frequently asked

Is CVE-2023-6816 being actively exploited?

CVE-2023-6816 is not in the CISA KEV catalog. Its EPSS exploit probability is 2.11%.

How severe is CVE-2023-6816?

CVE-2023-6816 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 2.11% probability of exploitation.

Which products are affected by CVE-2023-6816?

Affected products include X.org X Server, X.org Xwayland, Debian Linux, Fedoraproject Fedora, Redhat Enterprise Linux Desktop, and 2 more.

How do I fix CVE-2023-6816?

Upgrade affected software to a fixed version, for example X.org X Server 21.1.11, X.org Xwayland 23.2.4 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2023-6816 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.