CVE-2023-6816

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 v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
x.org	x_server	< 21.1.11
x.org	xwayland	< 23.2.4
fedoraproject	fedora	All
redhat	enterprise_linux_desktop	All
redhat	enterprise_linux_server	All
redhat	enterprise_linux_workstation	All
debian	debian_linux	All

References

Other References

https://access.redhat.com/errata/RHSA-2024:0320 https://access.redhat.com/errata/RHSA-2024:0557 https://access.redhat.com/errata/RHSA-2024:0558 https://access.redhat.com/errata/RHSA-2024:0597 https://access.redhat.com/errata/RHSA-2024:0607 https://access.redhat.com/errata/RHSA-2024:0614 https://access.redhat.com/errata/RHSA-2024:0617 https://access.redhat.com/errata/RHSA-2024:0621 https://access.redhat.com/errata/RHSA-2024:0626 https://access.redhat.com/errata/RHSA-2024:0629

Frequently Asked Questions

What is CVE-2023-6816? +

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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2023-6816? +

CVE-2023-6816 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2023-6816? +

CVE-2023-6816 affects products from debian, fedoraproject, redhat, x.org, specifically: debian_linux, enterprise_linux_desktop, enterprise_linux_server, enterprise_linux_workstation, fedora, x_server, xwayland. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6816? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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