Monday, March 31, 2025

The ClamAV 1.5.0 beta is now available. You may find the source code and installers for this release at clamav.net/downloads or on the ClamAV GitHub release page.

The beta phase is expected to last two to four weeks before we publish the stable release or else publish a release candidate. This will depend on how many changes are required to stabilize this version. Please take this time to evaluate ClamAV 1.5.0.

Please help us validate this release by providing feedback via GitHub issues, via the ClamAV mailing list or on our Discord.

IMPORTANT: A major feature of the 1.5 release is a FIPS-compliant method for verifying the authenticity of CVD signature database archives and CDIFF signature database patch files. The feature is ready to test in this beta, but we are not yet distributing the associated “.cvd.sign” signature files for the daily, main, and bytecode databases. Because these files aren’t available, ClamAV will fall back to using the legacy MD5-based RSA signature check. In other words, Freshclam will continue to fail on FIPS-enabled systems, for now. However, the unit tests do include a test signing key and certificate pair along with tests to exercise signing and verification using the FIPS-compliant method.

Note: Windows builds on GitHub Actions, which use VCPkg to provide C library dependencies, are failing at this time.

Tip: If you are downloading the source from the GitHub release page, the package labeled "clamav-1.5.0-beta.tar.gz" does not require an internet connection to build. All dependencies are included in this package. However, if you download the ZIP or TAR.GZ generated by GitHub, located at the very bottom, then an internet connection will be required during the build to download additional Rust dependencies.

For Docker users, there is no specific Docker tag for the beta, but you can use the clamav:unstable or clamav:unstable_base tags.

ClamAV 1.5.0 includes the following improvements and changes:

Major changes

  • Added checks to determine if an OLE2-based Microsoft Office document is encrypted.
  • Added the ability to record URLs found in HTML if the generate-JSON-metadata feature is enabled. Also adds an option to disable this in case you want the JSON metadata feature but don't want to record HTML URL's. The ClamScan command-line option is “--json-store-html-urls=no”. The clamd.conf config option is “JsonStoreHTMLUrls no”.
  • Added regex support for the clamd.conf OnAccessExcludePath config option. This change courtesy of GitHub user b1tg.
  • Added FIPS-compliant CVD signing/verification with external .sign files.
    Freshclam will now attempt to download external signature files to accompany existing .cvd databases and .cdiff patch files. Sigtool now has commands to sign and verify using the external signatures.

    ClamAV now installs a 'certs' directory in the app config directory (e.g. <prefix>/etc/certs). The install path is configurable. The CMake option to configure the CVD certs directory is “-D CVD_CERTS_DIRECTORY=PATH”. 

    Added sign/verify commands to Sigtool.

    New options to set an alternative CVD certs directory:
    - The command-line option for Freshclam, ClamD, ClamScan, and Sigtool is: --cvdcertsdir PATH
    - The environment variable for Freshclam, ClamD, ClamScan, and Sigtool is: CVD_CERTS_DIR

    The config option for Freshclam and ClamD is: CVDCertsDirectory PATH

    Added two new APIs to the public clamav.h header:
    extern cl_error_t cl_cvdverify_ex(const char *file, 
                                      const char *certs_directory);
    extern cl_error_t cl_cvdunpack_ex(const char *file, 
                                      const char *dir, 
                                      bool dont_verify, 
                                      const char *certs_directory); 


    The original cl_cvdverify and cl_cvdunpack are deprecated. 

    Added a cl_engine_field enum option CL_ENGINE_CVDCERTSDIR. You may set this option with cl_engine_set_str and get it with cl_engine_get_str to override the compiled in default CVD certs directory.

    Thank you to Mark Carey at SAP for inspiring work on this feature with an initial proof of concept for external-signature FIPS compliant CVD signing. 

Other improvements

  • Set a limit on the max-recursion config option. Users will no longer be able to set max-recursion higher than 100. This change prevents errors on start up or possible crashes if encountering a file with that many layers of recursion.
  • Build system: CMake improvements to support compiling for the AIX platform. This change is courtesy of GitHub user KamathForAIX.
  • Improve support for extracting malformed .zip archives. This change is courtesy of Frederick Sell.
  • Windows: Code quality improvement for the ClamScan and ClamDScan --move and --remove options. This change is the courtesy of Maxim Suhanov.
  • Added file type recognition for some kinds of AI model files.

    The file type appears as a string parameter for these callback functions:
      - clcb_pre_cache
      - clcb_pre_scan
      - clcb_file_inspection

    When scanning these files, the `type` parameter will now show "CL_TYPE_AI_MODEL" instead of "CL_TYPE_BINARY_DATA".

Bug fixes

  • Technical debt: Reduced email multipart message parser complexity.
  • Fixed possible undefined behavior in inflate64 module. The inflate64 module is a modified version of the zlib library, taken from version 1.2.3 with some customization and with some cherry-picked fixes. This adds one additional fix from zlib 1.2.9. Thank you to TITAN Team for reporting this issue.
  • Fixed a bug in ClamD that broke reporting of memory usage on Linux. The STATS command can be used to monitor ClamD directly or through ClamDTOP. The memory stats feature does not work on all platforms (e.g. Windows).
  • Windows: Fix a build issue when the same library dependency is found in two different locations.
  • Fix an infinite loop when scanning some email files in debug-mode. This fix is courtesy of Yoann Lecuyer

Acknowledgments

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

  • b1tg
  • Frederick Sell
  • KamathForAIX
  • Mark Carey at SAP
  • Maxim Suhanov
  • TITAN Team
  • Yoann Lecuyer


Thursday, March 27, 2025

ClamAV version 0.103 will reach its end of life (EOL) for database updates on September 14, 2025. After this date, this version will no longer receive the latest virus definitions. 

To ensure your systems remain protected, please upgrade to the latest supported version of ClamAV before the end-of-life date. This will provide continued access to essential security updates and features. 

We recommend that users update to the newest release, ClamAV 1.4 LTS. For users that are unable to upgrade to version 1.4, you may find that ClamAV 1.0 LTS is more suitable. The most recent version of ClamAV can be found on the ClamAV Downloads page, on the ClamAV GitHub Releases page, and through Docker Hub. Information about how to install ClamAV is available in our online documentation

The following is a list of major changes available to users in the newest versions of ClamAV. 

ClamAV 1.0 LTS improves upon ClamAV 0.103 with features such as: 

  • A new detection capability based on comparing image fuzzy hashes 
  • [Windows] A feature to start ClamD and Freshclam as Windows services 
  • [Windows] A feature to scan process memory with either ClamScan or ClamDScan 
  • Signature database load progress bars for ClamScan 
  • Support for extracting images from OLE2-based Excel documents 
  • The ability to use *.cat files with CRB signature rules to trust signed Windows executables 
  • Support for decrypting read-only OLE2-based XLS files that are encrypted with the default password 
  • Significant reliability improvements to the All-Match scanning mode Multiple libclamav API improvements

ClamAV 1.4 LTS improves upon ClamAV 1.0 with features such as: 

  • Support for extracting Universal Disk Format (UDF) partitions
  • Support for extracting ALZ archives 
  • Support for extracting LHA/LZH archives 
  • Support for extracting images embedded in HTML CSS style-blocks 
  • Support for extracting attachments found in Microsoft OneNote files 
  • An option to customize the size of ClamAV's clean file cache 
  • Effective removal of the MaxScanSize limit so the total amount of data scanned when scanning a file or archive may exceed 4GB. Note: This does not allow individual file size to exceed the 2GB limit 
  • The ability for Freshclam to use a client certificate PEM file and a private key PEM file for authentication to a private mirror 
  • A new ClamScan and ClamD option to fail to load if the provided signature database is older than a given number of days 
  • Multiple libclamav API improvements 

You can learn more about ClamAV's End of Life policy here. If you have any questions, please ask on our mailing list or in the ClamAV Discord.  

Thank you for your continued support.  


 


 

Wednesday, January 22, 2025

Today, we are publishing the 1.4.2 and 1.0.8 security patch versions. The release files for the patch versions are available for download on the ClamAV downloads page, on the GitHub Release page, and through Docker Hub. The images on Docker Hub may not be immediately available on release day. Continue reading to learn what changed in each version.


1.4.2

ClamAV 1.4.2 is a patch release with the following fixes: 
  • CVE-2025-20128: Fixed a possible buffer overflow read bug in the OLE2 file parser that could cause a denial-of-service (DoS) condition.

    This issue was introduced in version 1.0.0 and affects all currently supported versions. It will be fixed in: 1.4.2 and 1.0.8

    Thank you to OSS-Fuzz for identifying this issue.

1.0.8

ClamAV 1.0.8 is a patch release with the following fixes:
  • CVE-2025-20128: Fixed a possible buffer overflow read bug in the OLE2 file parser that could cause a denial-of-service (DoS) condition.

    This issue was introduced in version 1.0.0 and affects all currently supported versions. It will be fixed in: 1.4.2 and 1.0.8

    Thank you to OSS-Fuzz for identifying this issue.

  • ClamOnAcc: Fixed an infinite loop when a watched directory does not exist. This is a backport of a fix from ClamAV 1.3.0.

Wednesday, January 8, 2025

We are excited to announce that ClamAV 1.4 is now designated as our latest Long-Term Stable (LTS) release. 

Previously, we planned to announce 1.5 as the next LTS version at the end of 2024. However, unforeseen challenges have delayed the 1.5 release, leading us to choose version 1.4 for long-term support. We apologize for any inconvenience that our delay in the announcement may have caused. The version support dates for ClamAV 1.4 are amended as follows: 

Key Dates: 

  • Initial 1.4 Release Date: August 15, 2024 
  • Patch Versions Continue Until: August 15, 2027 
  • DB Downloads Allowed Until: August 15, 2028 

For specific details, please read the ClamAV EOL Policy

Looking ahead, the beta version of ClamAV 1.5 will soon be available for community review. This version will focus on resolving FIPS mode compatibility issues for newer distributions, such as Red Hat Enterprise Linux 9. Stay tuned for further updates. 

Thank you for your continued support. 


Wednesday, September 4, 2024

Today, we are publishing the 1.4.1, 1.3.2, 1.0.7, and 0.103.12 security patch versions.

The release files for the patch versions are available for download on the ClamAV downloads page, on the GitHub Release page, and (with exception to 0.103.12) through Docker Hub.

The images on Docker Hub may not be immediately available on release day.

Continue reading to learn what changed in each version.

1.4.1

ClamAV 1.4.1 is a critical patch release with the following fixes:

  • CVE-2024-20506: Changed the logging module to disable following symlinks on Linux and Unix systems so as to prevent an attacker with existing access to the 'clamd' or 'freshclam' services from using a symlink to corrupt system files.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to Detlef for identifying this issue.

  • CVE-2024-20505: Fixed a possible out-of-bounds read bug in the PDF file parser that could cause a denial-of-service (DoS) condition.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to OSS-Fuzz for identifying this issue.

  • Removed unused Python modules from freshclam tests including deprecated 'cgi' module that is expected to cause test failures in Python 3.13.


1.3.2

ClamAV 1.3.2 is a patch release with the following fixes:

  • CVE-2024-20506: Changed the logging module to disable following symlinks on Linux and Unix systems so as to prevent an attacker with existing access to the 'clamd' or 'freshclam' services from using a symlink to corrupt system files.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to Detlef for identifying this issue.

  • CVE-2024-20505: Fixed a possible out-of-bounds read bug in the PDF file parser that could cause a denial-of-service condition.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to OSS-Fuzz for identifying this issue.

  • Removed unused Python modules from freshclam tests including deprecated 'cgi' module that is expected to cause test failures in Python 3.13.

  • Fix unit test caused by expiring signing certificate.

  • Fixed a build issue on Windows with newer versions of Rust. Also upgraded GitHub Actions imports to fix CI failures. Fixes courtesy of liushuyu.

  • Fixed an unaligned pointer dereference issue on select architectures. Fix courtesy of Sebastian Andrzej Siewior.

  • Fixes to Jenkins CI pipeline.

For details, see GitHub pull request


1.0.7

ClamAV 1.0.7 is a patch release with the following fixes:

  • CVE-2024-20506: Changed the logging module to disable following symlinks on Linux and Unix systems so as to prevent an attacker with existing access to the 'clamd' or 'freshclam' services from using a symlink to corrupt system files.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to Detlef for identifying this issue.

  • CVE-2024-20505: Fixed a possible out-of-bounds read bug in the PDF file parser that could cause a denial-of-service (DoS) condition.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to OSS-Fuzz for identifying this issue.

  • Removed unused Python modules from freshclam tests including deprecated 'cgi' module that is expected to cause test failures in Python 3.13.

  • Fix unit test caused by expiring signing certificate.

  • Fixed a build issue on Windows with newer versions of Rust. Also upgraded GitHub Actions imports to fix CI failures. Fixes courtesy of liushuyu.

  • Fixed an unaligned pointer dereference issue on select architectures. Fix courtesy of Sebastian Andrzej Siewior.

  • Fixes to Jenkins CI pipeline.

For details, see GitHub pull request


0.103.12

ClamAV 0.103.12 is a patch release with the following fixes:

  • CVE-2024-20506: Changed the logging module to disable following symlinks on Linux and Unix systems so as to prevent an attacker with existing access to the 'clamd' or 'freshclam' services from using a symlink to corrupt system files.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to Detlef for identifying this issue.

  • CVE-2024-20505: Fixed a possible out-of-bounds read bug in the PDF file parser that could cause a denial-of-service condition.

    This issue affects all currently supported versions. It will be fixed in:

    • 1.4.1
    • 1.3.2
    • 1.0.7
    • 0.103.12

    Thank you to OSS-Fuzz for identifying this issue.

  • ClamOnAcc: Fixed an infinite loop when a watched directory does not exist.

  • Fixed a bug causing CVDs downloaded by the DatabaseCustomURL Freshclam config option to be pruned and then re-downloaded with every update. Also added the new 'valhalla' database name to the list of optional databases in preparation for future work.

  • Fixed an unaligned pointer dereference issue on select architectures. Fix courtesy of Sebastian Andrzej Siewior.


Thursday, August 15, 2024

The ClamAV 1.4.0 feature release is now stable. We encourage everyone to download the latest version now from the ClamAV downloads page, on the GitHub Release page, and through Docker Hub*:

*The Docker images are built on release day and will be made available when they are ready.

We are also publishing ClamAV bytecode compiler version 1.4.0.

The ClamAV bytecode compiler release files are available for download on the GitHub Release page and through Docker Hub.

ClamAV platform support changes

We will no longer provide Linux 32-bit packages. With RHEL 7 reaching end-of-life, we had to upgrade our build hosts and selected Alma Linux 8. Alma Linux does not provide 32-bit images. ClamAV users on 32-bit platforms can still build from source.

We now provide ARM64 packages for Windows. We are not able to provide ARM64/aarch64
Linux packages for this release.

Regarding future versions

An expired signing certificate used to create one of the test files is causing feature test failures in previous versions (1.3.1, 1.0.6 LTS). This is only a test issue and does not impact ClamAV functionality or detection. We are preparing patch versions for the 1.3 and 1.0 feature releases to address the test issue.

The next LTS release will be announced later this year. It will likely be the feature release after 1.4.

The 0.103 LTS release will soon reach end-of-life for security fixes. Check out our recent blog post for full details


Continue reading to learn what changed in these versions.

ClamAV 1.4.0

ClamAV 1.4.0 includes the following improvements and changes:

Major changes

  • Added support for extracting ALZ archives. The new ClamAV file type for ALZ archives is CL_TYPE_ALZ. Added a DCONF option to enable or disable ALZ archive support.

    Tip: DCONF (Dynamic CONFiguration) is a feature that allows for some configuration changes to be made via ClamAV .cfg "signatures".

  • Added support for extracting LHA/LZH archives. The new ClamAV file type for LHA/LZH archives is CL_TYPE_LHA_LZH. Added a DCONF option to enable or disable LHA/LZH archive support.

  • Added the ability to disable image fuzzy hashing, if needed. For context, image fuzzy hashing is a detection mechanism useful for identifying malware by matching images included with the malware or phishing email/document.

    New ClamScan options:

    --scan-image[=yes(*)/no]
    --scan-image-fuzzy-hash[=yes(*)/no]
    

    New ClamD config options:

    ScanImage yes(*)/no
    ScanImageFuzzyHash yes(*)/no
    

    New libclamav scan options:

    options.parse &= ~CL_SCAN_PARSE_IMAGE;
    options.parse &= ~CL_SCAN_PARSE_IMAGE_FUZZY_HASH;
    

    Added a DCONF option to enable or disable image fuzzy hashing support.

Other improvements

  • Added cross-compiling instructions for targeting ARM64/aarch64 processors for Windows and Linux.

  • Improved the Freshclam warning messages when being blocked or rate limited to include the Cloudflare Ray ID, which helps with issue triage.

  • Removed unnecessary memory allocation checks when the size to be allocated is fixed or comes from a trusted source. We also renamed internal memory allocation functions and macros, so it is more obvious what each function does.

  • Improved the Freshclam documentation to make it clear that the --datadir option must be an absolute path to a directory that already exists, is writable by Freshclam, and is readable by ClamScan and ClamD.

  • Added an optimization to avoid calculating the file hash if the clean file cache has been disabled. The file hash may still be calculated as needed to perform hash-based signature matching if any hash-based signatures exist that target a file of the same size, or if any hash-based signatures exist that target "any" file size.

  • Added an improvement to the SystemD service file for ClamOnAcc so that the service will shut down faster on some systems.

  • Added a CMake build dependency on the version map files so that the build will re-run if changes are made to the version map files. Work courtesy of Sebastian Andrzej Siewior.

  • Added an improvement to the CMake build so that the RUSTFLAGS settings are inherited from the environment. Work courtesy of liushuyu.

Bug fixes

  • Silenced confusing warning message when scanning some HTML files.

  • Fixed minor compiler warnings.

  • Since the build system changed from Autotools to CMake, ClamAV no longer supports building with configurations where bzip2, libxml2, libz, libjson-c, or libpcre2 are not available. Libpcre is no longer supported in favor of libpcre2. In this release, we removed all the dead code associated with those unsupported build configurations.

  • Fixed assorted typos. Patch courtesy of RainRat.

  • Added missing documentation for the ClamScan --force-to-disk option.

  • Fixed an issue where ClamAV unit tests would prefer an older libclamunrar_iface library from the install path, if present, rather than the recently compiled library in the build path.

  • Fixed a build issue on Windows with newer versions of Rust. Also upgraded GitHub Actions imports to fix CI failures. Fixes courtesy of liushuyu.

  • Fixed an unaligned pointer dereference issue on select architectures. Fix courtesy of Sebastian Andrzej Siewior.

  • Fixed a bug that prevented loading plaintext (non-CVD) signature files when using the --fail-if-cvd-older-than=DAYS / FailIfCvdOlderThan option. Fix courtesy of Bark.

Acknowledgments

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

  • Bark
  • liushuyu
  • Sebastian Andrzej Siewior
  • RainRat

ClamAV Bytecode Compiler 1.4.0

➕ Upgrade bytecode compiler project to LLVM 16.

🌌 New Requirements:

  • LLVM 16
  • Clang 16