CVE-2026-105243

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...

CVE-2026-105243 Apache log4net: Oversize EventLogAppender record silently discarded

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...

CVE-2026-105243 Apache log4net: Oversize EventLogAppender record silently discarded

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...

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-2026-105242 Apache log4net: Request validation failure drops the event in the aspnet-request converter

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A...

EUVD-2026-93867

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A...

CVE-2026-105242

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A...

CVE-2026-105242 Apache log4net: Request validation failure drops the event in the aspnet-request converter

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A...

CVE-2026-105242 Apache log4net: Request validation failure drops the event in the aspnet-request converter

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A...

CVE-2026-105242

The Apache log4net logging framework (versions 1.2.11 through 3.5.0 ) is vulnerable to an Improper Handling of Exceptional Conditions (CWE-755) in the aspnet-request pattern converter. When reading request parameters, certain content—such as markup—triggers ASP.NET request validation , causing th...

EUVD-2026-93866

Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content,...

CVE-2026-105241 Apache log4net: Unencodable content discards a whole SmtpPickupDirAppender batch

Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content,...

CVE-2026-105241

Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content,...

CVE-2026-105241 Apache log4net: Unencodable content discards a whole SmtpPickupDirAppender batch

Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content,...

CVE-2026-105241 Apache log4net: Unencodable content discards a whole SmtpPickupDirAppender batch

Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content,...

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...

CVE-2026-105240 Apache log4net: NUL character truncates OutputDebugStringAppender records

Improper Neutralization of Null Byte or NUL Character vulnerability in the OutputDebugStringAppender of Apache log4net. A NUL character in logged content ended the debug output record at that point, so everything the layout rendered after it, including exception text and trailing fields, was...

EUVD-2026-93864

Improper Neutralization of Null Byte or NUL Character vulnerability in the OutputDebugStringAppender of Apache log4net. A NUL character in logged content ended the debug output record at that point, so everything the layout rendered after it, including exception text and trailing fields, was...

CVE-2026-105240

Improper Neutralization of Null Byte or NUL Character vulnerability in the OutputDebugStringAppender of Apache log4net. A NUL character in logged content ended the debug output record at that point, so everything the layout rendered after it, including exception text and trailing fields, was...

CVE-2026-105240 Apache log4net: NUL character truncates OutputDebugStringAppender records

Improper Neutralization of Null Byte or NUL Character vulnerability in the OutputDebugStringAppender of Apache log4net. A NUL character in logged content ended the debug output record at that point, so everything the layout rendered after it, including exception text and trailing fields, was...