Client crash via XIM attribute overread
Published Sep 28, 2026 · Updated Sep 28, 2026
Out-of-bounds reading in X.Org libX11 before 1.8.14 allows remote attackers controlling an X server to crash attached X clients. The X Input Method attribute parser reads outside the bounds of server-supplied attribute data; the public record does not identify the specific parser function or unchecked length. Exploitation requires an affected client to connect to the malicious X server and process its XIM attributes; the reported consequence is a client crash, not data access or code execution.
Summary
What happened
Out-of-bounds reading in X.Org libX11 before 1.8.14 allows remote attackers controlling an X server to crash attached X clients. The X Input Method attribute parser reads outside the bounds of server-supplied attribute data; the public record does not identify the specific parser function or unchecked length. Exploitation requires an affected client to connect to the malicious X server and process its XIM attributes; the reported consequence is a client crash, not data access or code execution.
The record
- CVE
- CVE-2026-94283
- Published
- Sep 28, 2026
- Updated
- Sep 28, 2026
- Vendor
- The X11 Project
- Product
- libX11
- Classifications
- CWE-125, CAPEC-540, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 28, 2026CVE publishedPublication date reported by the CVE source.
- Sep 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <1.8.14
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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