Logback 1.5.27

2026-01-30 Release of logback version 1.5.27

• Updated license to Eclipse Public License version 2.0 from version 1.0, retaining the GPL 2.1 dual-license.

• Fixed missing MDC data transmitted by SocketAppender reported in issues/1010 by Lars Vogel.

• Removed all Receiver classes and components which were already disabled for several years.

• Refactored file scanning code for improved clarity.

• In SizeAndTimeBasedRollingPolicy modified totalSizeCap and maxFileSize comparison to taking into account file compression. This fixes issues/1007.

• A bit-wise identical binary of this version can be reproduced by building from source code at commit 3618eb01aad6672f9cd250dccf7546a69cbe982f associated with the tag v_1.5.27. Release built using Java "21" 2023-10-17 LTS build 21.0.1.+12-LTS-29 under Linux Debian 11.6.

Logback 1.5.26

2026-01-25 Release of logback version 1.5.26

• InsertFromJNDIModelHandler was accessing javax.naming package forcing the inclusion of the optional java.naming module. This problem was raised in issues/1003 by Marius Hanl who also provided the relevant PR.

• In applications using shadow/fat/shade jars, module or package information could be lost. Thus, in the absence of version information, logback-classic would warn about version mismatches. Logback components now ship with properties files containing version information that survive shadow/fat/shade jars. This issue was reporteed in issues/1002 by Christoph Gritschenberger.

• A bit-wise identical binary of this version can be reproduced by building from source code at commit 33deb54506bbfaf1ff151f26f3a5f86936011619 associated with the tag v_1.5.26. Release built using Java "21" 2023-10-17 LTS build 21.0.1.+12-LTS-29 under Linux Debian 11.6.

Logback 1.5.25

2026-01-17 Release of logback version 1.5.25

• When processing configuration files, logback-core will now only instantiate components compatible with the class expected by the encapsulating class. This fixes an ACE vulnerability recorded as CVE-2026-1225.

• In configuration files, referencing a single undeclared appender would cause all referenced appenders to be skipped. This issue was discovered in issues/997.

• Added VersionUtil class to logback-core. This utility class checks for version compatibility issues and alerts the user if need be.

• Added EpochConverter to output milliseconds/seconds since epoch. This enhancement was requested by Duncan Jauncey in issues/1000 who also provided the relevant implementation PR.

• A bit-wise identical binary of this version can be reproduced by building from source code at commit f426e0002800cfb507f393fcacffe0761a425220 associated with the tag v_1.5.25. Release built using Java "21" 2023-10-17 LTS build 21.0.1.+12-LTS-29 under Linux Debian 11.6.

Logback 1.5.24

2026-01-06 Release of logback version 1.5.24

• Added ExpressionPropertyCondition a PropertyCondition that can evaluate boolean expressions similar to Java. See the relevant documentation for further details.

• A bit-wise identical binary of this version can be reproduced by building from source code at commit 62bc5fc245dd3a52f3dd45e232733f4cefb4806d associated with the tag v_1.5.24. Release built using Java "21" 2023-10-17 LTS build 21.0.1.+12-LTS-29 under Linux Debian 11.6.

Logback 1.5.23

2025-12-21 Release of logback version 1.5.23

• In response to issues/959 file name collisions are detected at configuration time by analyzing the configuration file and no longer at run time. This avoids the ConcurrentModificationException reported in the issue.

• ZIP and XZ compression now use a BufferedOutputStream when writing to the compressed file. This issue was reported in issues/988.