Today we are publishing a second release candidate for ClamAV 1.0.0. If you haven't gotten a chance to test the 1.0.0 release candidate yet, please have a look before we publish the stable release. You can find the ClamAV 1.0.0-rc2 release candidate files on the ClamAV.net Downloads page.

We expect to publish the stable 1.0.0 release in two weeks.

Today we are also publishing updated packages for ClamAV 0.105.1.

The new packages have a "-3" suffix to indicate the package revision. For example, clamav-0.105.1-3.macos.universal.pkg is the updated package replacing clamav-0.105.1-2.macos.universal.pkg.

As always, you can get the updated packages from the ClamAV.net Downloads page. The original packages have been hidden on the web page and replaced by the updated packages. If you need the originals, the URLs to download them still work.

ClamAV 1.0.0-rc2 includes the following improvements and changes.

Major changes:

• Support for decrypting read-only OLE2-based XLS files that are encrypted with the default password. Use of the default password will now appear in the metadata JSON.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/700

• Overhauled the implementation of the all-match feature. The newer code is more reliable and easier to maintain.

  • This project fixed several known issues with signature detection in all- match mode:

    • Enabled embedded file-type recognition signatures to match when a malware signature also matched in a scan of the same layer.

    • Enabled bytecode signatures to run in all-match mode after a match has occurred.

    • Fixed an assortment of all-match edge case issues.

  • Added multiple test cases to verify correct all-match behavior.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/687

• Added a new callback to the public API for inspecting file content during a scan at each layer of archive extraction.

  • The new callback function type is clcb_file_inspection defined in clamav.h.

  • The function cl_engine_set_clcb_file_inspection() may be used to enable the callback prior to performing a scan.

  • This new callback is to be considered unstable for the 1.0 release. We may alter this function in a subsequent feature version.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/170

• Added a new function to the public API for unpacking CVD signature archives.

  • The new function is cl_cvdunpack(). The last parameter for the function may be set to verify if a CVD's signature is valid before unpacking the CVD content to the destination directory.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/690

• The option to build with an external TomsFastMath library has been removed. ClamAV requires non-default build options for TomsFastMath to support bigger floating point numbers. Without this change, database and Windows EXE/DLL authenticode certificate validation may fail. The ENABLE_EXTERNAL_TOMSFASTMATH build is now ignored.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/742

Other improvements:

• Add checks to limit PDF object extraction recursion.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/629

• Increased the limit for memory allocations based on untrusted input and altered the warning message when the limit is exceeded so that it is more helpful and less dramatic.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/723

• Dramatically improved the build time of libclamav-Rust unit tests. The unit test build is included in the time limit for the test itself and was timing out on slower systems. The ClamAV Rust code modules now share the same build directory, which also reduces the amount of disk space used for the build.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/694

• For Windows: The debugging symbol (PDB) files are now installed alongside the DLL and LIB library files when built in "RelWithDebInfo" or "Debug" mode.

• GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/669

• Relaxed the constraints on the check for overlapping ZIP file entries so as not to alert on slightly malformed, but non-malicious, Java (JAR) archives.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/561

Talos escalations issues:

• Increased the time limit in FreshClam before warning if the DNS entry is stale. In combination with changes to update the DNS entry more frequently, this should prevent false alarms of failures in the database publication system.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/597

• Docker: The C library header files are now included in the Docker image. Patch courtesy of GitHub user TerminalFi.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/693

• Show the BYTECODE_RUNTIME build options when using the ccmake GUI for CMake. Patch courtesy of Дилян Палаузов.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/678

• Added explicit minimum and maximum supported LLVM versions so that the build will fail if you try to build with a version that is too old or too new and will print a helpful message rather than simply failing to compile because of compatibility issues. Patch courtesy of Matt Jolly.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/692

Bug fixes:

• Assorted code quality fixes. These are not security issues and will not be backported to prior feature versions:

  • Several heap buffer overflows while loading PDB and WDB databases were found by OSS-Fuzz and by Michał Dardas.

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/530

    • Follow-up Optimization: https://github.com/Cisco-Talos/clamav/pull/712

  • oss-fuzz 43843: heap buffer overflow read (1) cli_sigopts_handler

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/560

  • oss-fuzz 44849: heap buffer overflow read (4) in HTML/js-norm

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/503

  • oss-fuzz 43816: heap buffer overflow read (8) in cli_bcomp_freemeta

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/583

  • oss-fuzz 43832: heap buffer overflow read (2) in cli_parse_add

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/611

  • oss-fuzz 44493: integer overflow in cli_scannulsft

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/554

  • CIFuzz leak detected in IDB parser

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/547

  • oss-fuzz assorted signature parser leaks

    • GitHub pull requests:

      • https://github.com/Cisco-Talos/clamav/pull/532

      • https://github.com/Cisco-Talos/clamav/pull/533

      • https://github.com/Cisco-Talos/clamav/pull/535

  • oss-fuzz 40601: leak detected in pdf_parseobj

    • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/553

• Fixed a build failure when using LIBCLAMAV_ONLY mode with tests enabled.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/714

• Fixed an issue verifying EXE/DLL authenticode signatures to determine a given file can be trusted (skipped).

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/727

• Fixed a caching bug relating to the Container and Intermediates logical signature condition.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/724

• Fixed a build issue when build with RAR disabled or when building with an external libmspack library rather than the vendor library.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/672

• Fixed the capitalization of the -W option for clamonacc in the clamonacc manpage. Patch courtesy of GitHub user monkz.

  • GitHub pull requests:

    • https://github.com/Cisco-Talos/clamav/pull/709

    • https://github.com/Cisco-Talos/clamav/pull/710

• macOS: Fixed an issue with memory-map (mmap) system call detection affecting versions 0.105 and 0.104. Memory maps may be used in ClamAV to improve signature load performance and scan performance, as well as RAM usage.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/705

• Fixed a performance issue with Rust code when the build type is not explicitly set to "Release" or "RelWithDebInfo". The Rust default build type is now "RelWithDebInfo" just like the C code, instead of Debug. This means it is now optimized by default.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/701

• Fixed an issue loading Yara rules containing regex strings with an escaped forward-slash (\/) followed by a colon (:).

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/696

• Fixed an issue detecting and scanning ZIP file entries appended to very small files. The fix is part of the all-match feature overhaul.

• Fixed a detection issue with EXE/DLL import-address-table hash signatures that specify a wildcard (*) for the size field. The fix is part of the all-match feature overhaul.

• Fixed the default bytecode timeout value listed in the manpages and in the sample config files. Patches courtesy of Liam Jarvis and Ben Bodenmiller.

  • GitHub pull requests:

    • https://github.com/Cisco-Talos/clamav/pull/631

    • https://github.com/Cisco-Talos/clamav/pull/661

• Fixed an issue building the libclamav_rust test program when running ctest if building with BYTECODE_RUNTIME=llvm and when the FindLLVM.cmake module is used to find the LLVM libraries. Patch courtesy of GitHub user teoberi.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/572

• Fixed an issue where scans sent to clamd with the all-match mode enabled caused all subsequent scans to also use all-match mode.

  • GitHub pull request: https://github.com/Cisco-Talos/clamav/pull/741

Acknowledgments

Special thanks to the following people for code contributions and bug reports:

• Ben Bodenmiller

• Дилян Палаузов

• Liam Jarvis

• Matt Jolly

• monkz

• teoberi

• TerminalFi