CVE-2026-33999

Publication date 14 April 2026

Last updated 16 April 2026


Ubuntu priority

Description

XKB Integer Underflow in XkbSetCompatMap(). If a "compat" buffer was previously truncated, there will be unused space left in the buffer. The code in XkbSetCompatMap() will use that space, but fails to update the number of valid entries actually in the buffer. As a result, that can lead to buffer read overrun when processing a future request.

Read the notes from the security team

Status

Package Ubuntu Release Status
xorg 25.10 questing
Not affected
24.04 LTS noble
Not affected
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
xorg-server 25.10 questing
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
xwayland 25.10 questing
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
xorg-server-hwe-16.04 25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
16.04 LTS xenial
Needs evaluation
xorg-server-hwe-18.04 25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Needs evaluation
xorg-hwe-16.04 25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
16.04 LTS xenial
Not affected
xorg-hwe-18.04 25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Not affected

Notes


mdeslaur

xorg server is actually the xorg-server package the xorg package only contains docs xwayland package contains parts of xorg-server


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