CVE-2026-105239

The Apache log4net library (versions 1.2.9 through 3.5.0) is vulnerable to an Improper Neutralization of Null Byte or NUL Character in the EventLogAppender . When a NUL character is present in logged content, it prematurely terminates the Windows Event Log record, causing subsequent data—such as ...

CVE-2026-105243

The Apache log4net logging framework (versions 1.2.9 before 3.5.0 ) contains an Insufficient Logging vulnerability in the EventLogAppender component on Windows. The root cause is that long messages are truncated to a fixed size that exceeds the Windows Event Log capacity once log and source names...

CVE-2026-105240

The Apache log4net logging framework (versions 1.2.9 before 3.5.0) is vulnerable to an Improper Neutralization of Null Byte or NUL Character (CWE-158) within the OutputDebugStringAppender . On Windows systems, a NUL character in logged content causes the debug output record to truncate prematurel...

CVE-2026-105241

The Apache log4net logging framework (versions 1.2.9 before 3.5.0 ) is vulnerable to an Improper Handling of Unicode Encoding issue within the SmtpPickupDirAppender component. If the mail file writer encounters content it cannot encode, such as an unpaired UTF-16 surrogate , it causes the write o...