Xorg: xwayland: x.org x server: denial of service via integer underflow in xkb compatibility map handling

Mariner

Read the vendor bulletin Get alerts for cbl2 xorg-x11-server 1.20.10-16 on CBL Mariner

6.6CVSS out of 10Medium severity

Scope

What the vendor says is affected

cbl2 xorg-x11-server 1.20.10-16 on CBL Mariner 2.0
azl3 xorg-x11-server-Xwayland 24.1.6-3 on Azure Linux 3.0

Timeline

When this advisory changed

Apr 29, 2026 at 1:11 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Sep 27, 2026 at 11:11 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.

Vulnerabilities

CVEs named in this advisory

CVE-2026-33999View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-33999
Last source check: Sep 27, 2026 at 11:11 PM UTC

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Your environment

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Watch cbl2 xorg-x11-server 1.20.10-16 on CBL Mariner

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What the vendor says is affected

When this advisory changed

CVEs named in this advisory

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