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log4net

3.5.0432M downloads/moapache/logging-log4net ↗New releases in your daily digest, changelog included.

log4net is a tool to help the programmer output log statements to a variety of output targets. In case of problems with an application, it is helpful to enable logging so that the problem can be located. With log4net it is possible to enable logging at runtime without modifying the application binary. The log4net package is designed so that log statements can remain in shipped code without incurring a high performance cost. It follows that the speed of logging (or rather not logging) is crucial. At the same time, log output can be so voluminous that it quickly becomes overwhelming. One of the distinctive features of log4net is the notion of hierarchical loggers. Using these loggers it is possible to selectively control which log statements are output at arbitrary granularity. log4net is designed with two distinct goals in mind: speed and flexibility

Last release 7 days ago
01 Oct 2026
Ships fairly regularly
a new release about every 2 months
Some releases are documented
notes for 5 of 20 stable releases
12 versions withdrawn
withdrawn after publishing
127 years old
32 releases · first in 1900

Release timeline

32 releases since 1900

Releases

3.5.01 Oct 2026
Recognise a native host as having no configuration system ( #162 ) by @FreeAndNil in #311
What's Changed

Recognise a native host as having no configuration system (#162) by @FreeAndNil in #311

Harden the release scripts and connection string redaction by @FreeAndNil in #313

Stop network appenders stalling and losing events by @FreeAndNil in #314

Escaping special characters in multiple appenders by @FreeAndNil in #315

Prevent the ANSI appender and %aspnet-request dropping events by @FreeAndNil in #316

Prevent content from steering the string match filters by @FreeAndNil in #317

Prevent Telnet clients reaching or stalling the application by @FreeAndNil in #318

Bump js-yaml, @antora/cli and @antora/site-generator-default by @dependabot[bot] in #320

file locking: keep the log on a failed roll, fix the mutex name by @FreeAndNil in #319

close the outgoing appenders before activating the new ones #321 by @FreeAndNil in #322

stop stale context reaching logical stacks and fixed events by @FreeAndNil in #323

stop appenders losing or leaking what they write by @FreeAndNil in #324

native interop: fix syslog on Apple arm64, stop starting getprop by @FreeAndNil in #325

one home for the reflection in the tests by @FreeAndNil in #326

Pester tests for build-release and build-preview by @FreeAndNil in #327

require transport security by default in the Ext.Mail SmtpAppender by @FreeAndNil in #329

report an unexpected Telnet send failure instead of dropping the client by @FreeAndNil in #331

bind a release to the commit it was built from by @FreeAndNil in #330

report who accepted the connection in ListenAddressBindsOnlyThatAddress by @FreeAndNil in #328

Full Changelog: rel/3.4.0...rc/3.5.0

Nuget

https://www.nuget.org/packages/log4net/3.5.0

https://www.nuget.org/packages/log4net.Ext.Mail/3.5.0

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3.4.021 Aug 2026

Bump js-yaml, @antora/cli and @antora/site-generator-default by @dependabot [bot] in #299

What's Changed

Bump js-yaml, @antora/cli and @antora/site-generator-default by @dependabot[bot] in #299
Pin js-yaml to ^4.3.0 via npm override by @FreeAndNil in #301
log4net.Ext.Mail by @FreeAndNil in #302
Fix LoggingEvent.UserName resolving the Windows identity for every event by @FreeAndNil in #304
dotnet 10 build cleanup by @FreeAndNil in #305
mark log4net.Ext.Mail as CLS compliant (#307) by @FreeAndNil in #307
bump js-yaml override to ^4.3.1 (#308) by @FreeAndNil in #308
make log4net usable from a PublishAOT build (#306) by @FreeAndNil in #306
Harden log4net against the findings of a security audit by @FreeAndNil in #310

Full Changelog: rel/3.3.2...rel/3.4.0

Nuget

Open source →

3.3.225 Jun 2026

Add Grzegorz Dziadkiewicz to list of active commiters by @gdziadkiewicz in #293

What's Changed

Add Grzegorz Dziadkiewicz to list of active commiters by @gdziadkiewicz in #293
Fix race in Hierarchy.TryCreateLogger by @gdziadkiewicz in #294
[INFRA] Set up default rulesets for default and release branches by @asf-gitbox-commits in #295
Fixes after AVSS scanning by @FreeAndNil in #298

New Contributors

@asf-gitbox-commits made their first contribution in #295

Full Changelog: rel/3.3.1...rel/3.3.2
Nuget: https://www.nuget.org/packages/log4net/3.3.2

Open source →

3.3.119 Apr 2026

Bump picomatch by @dependabot [bot] in #284

What's Changed

#281 fix hints and warnings by @FreeAndNil in #281
Bump picomatch by @dependabot[bot] in #284
Bump convict from 6.2.4 to 6.2.5 by @dependabot[bot] in #285
Bump handlebars from 4.7.8 to 4.7.9 by @dependabot[bot] in #286
Reduce silent log event loss during XmlConfigurator reconfiguration by @N0tre3l in #287
bump internal log4net version for GHSA-4f7c-pmjv-c25w #289 by @FreeAndNil in #289
preserve UTF-16 surrogate pairs in MaskXmlInvalidCharacters - fixes #290 by @FreeAndNil in #291

New Contributors

@N0tre3l made their first contribution in #287

Full Changelog: rel/3.3.0...rel/3.3.1
Nuget: https://www.nuget.org/packages/log4net/3.3.1

Open source →

3.3.020 Feb 2026

switch to macos-14 - mono no longer works on macos-15 by @FreeAndNil in #266

What's Changed

switch to macos-14 - mono no longer works on macos-15 by @FreeAndNil in #266
shorten console output for unit tests by @FreeAndNil in #268
Fix DllImport attribute for OutputDebugString function by @ban-dana in #270
Fix marshalling for OutputDebugString parameter, add unit test by @ban-dana in #271
Bump js-yaml from 4.1.0 to 4.1.1 by @dependabot[bot] in #272
Add versioning and support policy information by @FreeAndNil in #275
added NewLineHandling to RemoteSyslogAppender - fixes #274 by @FreeAndNil in #276
fixed flaky test Log4Net_WritesLogFile_WithDateAndSizeRoll_Config_Works by @FreeAndNil in #277
#280 harden the handling of invalid characters for the XmlLayout classes by @FreeAndNil in #280

New Contributors

@ban-dana made their first contribution in #270

Full Changelog: rel/3.2.0...rc/3.3.0-rc1
Nuget: https://www.nuget.org/packages/log4net/3.3.0

Open source →

3.2.022 Aug 2025