CVE-2026-105243 (GCVE-0-2026-105243)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:51 – Updated: 2026-10-06 19:51
VLAI
Title
Apache log4net: Oversize EventLogAppender record silently discarded
Summary
Insufficient Logging vulnerability in the EventLogAppender of Apache log4net. Long messages were truncated to a fixed size that exceeds what the Windows Event Log accepts once the log and source names are counted, and the event log then stored nothing and reported nothing. A party whose data reaches a log message could suppress the whole record by making it long enough. Only applications on Windows that use EventLogAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache log4net Affected: 1.2.9 , < 3.5.0 (semver)
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Apache Software Foundation Apache log4net Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 28fbfb25678c48a8cc5bc9b94ead0dddfc39ffed (git)
guessed Create a notification for this product.
Credits
The Apache Software Foundation Claude Security Jan Friedrich
Show details on NVD website
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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