CVE-2026-93542: Out-of-bounds read in libXi's XI2 class parsing via size_classes() and copy_classes()
Published Sep 24, 2026
·Updated
An out-of-bounds read in libXi's XI2 class parsing via sizeclasses() and copyclasses() in libXi before 1.8.4 could be used by malicous servers to crash the X client.
Affected Software
1 affected component
X.Org Foundation libXi<1.8.4
Event History
Sep 24, 2026
CVE Published
via MITRE·04:03 PM
Data Sourced
via MITRE·04:03 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·05:17 PM
DescriptionSeverityWeakness
Frequently Asked Questions
1
Which clients are exposed to this issue?
X clients that use libXi versions before 1.8.4 and connect to a malicious X server are exposed. The reported impact is a client crash.
2
What does an attacker need to exploit it?
An attacker needs to operate or control an X server that the target X client connects to. Exploitation requires user interaction because the client must connect to that malicious server.
3
Does the vulnerability affect confidentiality or integrity?
The supplied severity vector indicates no confidentiality or integrity impact. The impact is limited to availability through a crash of the X client.