CVE-2025-20128

A vulnerability in the Object Linking and Embedding 2 (OLE2) decryption routine of ClamAV could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to an integer underflow in a bounds check that allows for a heap buffer overflow read. An attacker could exploit this vulnerability by submitting a crafted file containing OLE2 content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to terminate the ClamAV scanning process, resulting in a DoS condition on the affected software. For a description of this vulnerability, see the . Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

A vulnerability in the Object Linking and Embedding 2 (OLE2) decryption routine of ClamAV could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to an integer underflow in a bounds check that allows for a heap buffer overflow read. An attacker could exploit this vulnerability by submitting a crafted file containing OLE2 content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to terminate the ClamAV scanning process, resulting in a DoS condition on the affected software. For a description of this vulnerability, see the . Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

• Update up to 1.4.3 LTS
  • CVE-2025-20260
  • CVE-2025-20234
  • CVE-2025-20128
  • CVE-2024-20505, CVE-2024-20506
  • CVE-2023-20197
  • CVE-2023-20212
  • CVE-2023-20032
  • CVE-2023-20052

• Update to 1.4.3 LTS
• CVE-2025-20260: Fixed a possible buffer overflow write bug in the PDF file parser
• CVE-2025-20234: Fixed a possible buffer overflow read bug in the UDF file parser
• CVE-2025-20128: Fixed a possible buffer overflow read bug in the OLE2 file parser
• 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

• Update to 1.0.9 LTS version
• CVE-2025-20260: Fixed a possible buffer overflow write bug in the PDF file parser
• CVE-2025-20128: Fixed a possible buffer overflow read bug in the OLE2 file parser
• 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
• CVE-2024-20290: Fixed a possible heap overflow read bug in the OLE2 file parser
• CVE-2024-20328: Fixed a possible command injection in the 'VirusEvent' feature of the clamd service
• CVE-2023-20197: Fixed a possible denial of service in the HFS+ parser
• CVE-2023-20212: Fixed a possible DoS in the AutoIT file parser
• CVE-2023-20052: Fixed a possible remote information leak in the DMG file parser

ClamAV OLE2 File Format Decryption Denial of Service Vulnerability. (CVE-2025-20128)

These are all security issues fixed in the clamav-1.4.2-1.1 package on the GA media of openSUSE Tumbleweed.

This update for clamav fixes the following issues:

New version 1.4.2:

• CVE-2025-20128, bsc#1236307: Fixed a possible buffer overflow read bug in the OLE2 file parser that could cause a denial-of-service (DoS) condition.

• Start clamonacc with --fdpass to avoid errors due to clamd not being able to access user files. (bsc#1232242)

• New version 1.4.1:

  • https://blog.clamav.net/2024/09/clamav-141-132-107-and-010312-security.html

• New version 1.4.0:

  • Added support for extracting ALZ archives.
  • Added support for extracting LHA/LZH archives.
  • 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.
  • https://blog.clamav.net/2024/08/clamav-140-feature-release-and-clamav.html

• New version 1.3.2:

  • 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.
  • CVE-2024-20505: Fixed a possible out-of-bounds read bug in the PDF file parser that could cause a denial-of-service condition.
  • 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.
  • Fixed an unaligned pointer dereference issue on select architectures.
  • Fixes to Jenkins CI pipeline.

• New Version: 1.3.1:

  • CVE-2024-20380: Fixed a possible crash in the HTML file parser that could cause a denial-of-service (DoS) condition.
  • Updated select Rust dependencies to the latest versions.
  • Fixed a bug causing some text to be truncated when converting from UTF-16.
  • Fixed assorted complaints identified by Coverity static analysis.
  • Fixed a bug causing CVDs downloaded by the DatabaseCustomURL
  • Added the new 'valhalla' database name to the list of optional databases in preparation for future work.

• New version: 1.3.0:

  • Added support for extracting and scanning attachments found in Microsoft OneNote section files. OneNote parsing will be enabled by default, but may be optionally disabled.
  • Added file type recognition for compiled Python ('.pyc') files.
  • Improved support for decrypting PDFs with empty passwords.
  • Fixed a warning when scanning some HTML files.
  • ClamOnAcc: Fixed an infinite loop when a watched directory does not exist.
  • ClamOnAcc: Fixed an infinite loop when a file has been deleted before a scan.

• New version: 1.2.0:

  • Added support for extracting Universal Disk Format (UDF) partitions.
  • Added an option to customize the size of ClamAV's clean file cache.
  • Raised the MaxScanSize limit so the total amount of data scanned when scanning a file or archive may exceed 4 gigabytes.
  • Added ability for Freshclam to use a client certificate PEM file and a private key PEM file for authentication to a private mirror.
  • Fix an issue extracting files from ISO9660 partitions where the files are listed in the plain ISO tree and there also exists an empty Joliet tree.
  • PID and socket are now located under /run/clamav/clamd.pid and /run/clamav/clamd.sock .
  • bsc#1211594: Fixed an issue where ClamAV does not abort the signature load process after partially loading an invalid signature.

• New version 1.1.0:

  • https://blog.clamav.net/2023/05/clamav-110-released.html
  • Added the ability to extract images embedded in HTML CSS

    <style> blocks.

  • Updated to Sigtool so that the '--vba' option will extract VBA code from Microsoft Office documents the same way that …

This update for clamav fixes the following issues:

New version 1.4.2:

• CVE-2025-20128, bsc#1236307: Fixed a possible buffer overflow read bug in the OLE2 file parser that could cause a denial-of-service (DoS) condition.

• Start clamonacc with --fdpass to avoid errors due to clamd not being able to access user files. (bsc#1232242)

• New version 1.4.1:

  • https://blog.clamav.net/2024/09/clamav-141-132-107-and-010312-security.html

• New version 1.4.0:

  • Added support for extracting ALZ archives.
  • Added support for extracting LHA/LZH archives.
  • 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.
  • https://blog.clamav.net/2024/08/clamav-140-feature-release-and-clamav.html

• New version 1.3.2:

  • 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.
  • CVE-2024-20505: Fixed a possible out-of-bounds read bug in the PDF file parser that could cause a denial-of-service condition.
  • 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.
  • Fixed an unaligned pointer dereference issue on select architectures.
  • Fixes to Jenkins CI pipeline.

• New Version: 1.3.1:

  • CVE-2024-20380: Fixed a possible crash in the HTML file parser that could cause a denial-of-service (DoS) condition.
  • Updated select Rust dependencies to the latest versions.
  • Fixed a bug causing some text to be truncated when converting from UTF-16.
  • Fixed assorted complaints identified by Coverity static analysis.
  • Fixed a bug causing CVDs downloaded by the DatabaseCustomURL
  • Added the new 'valhalla' database name to the list of optional databases in preparation for future work.

• New version: 1.3.0:

  • Added support for extracting and scanning attachments found in Microsoft OneNote section files. OneNote parsing will be enabled by default, but may be optionally disabled.
  • Added file type recognition for compiled Python ('.pyc') files.
  • Improved support for decrypting PDFs with empty passwords.
  • Fixed a warning when scanning some HTML files.
  • ClamOnAcc: Fixed an infinite loop when a watched directory does not exist.
  • ClamOnAcc: Fixed an infinite loop when a file has been deleted before a scan.

• New version: 1.2.0:

  • Added support for extracting Universal Disk Format (UDF) partitions.
  • Added an option to customize the size of ClamAV's clean file cache.
  • Raised the MaxScanSize limit so the total amount of data scanned when scanning a file or archive may exceed 4 gigabytes.
  • Added ability for Freshclam to use a client certificate PEM file and a private key PEM file for authentication to a private mirror.
  • Fix an issue extracting files from ISO9660 partitions where the files are listed in the plain ISO tree and there also exists an empty Joliet tree.
  • PID and socket are now located under /run/clamav/clamd.pid and /run/clamav/clamd.sock .
  • bsc#1211594: Fixed an issue where ClamAV does not abort the signature load process after partially loading an invalid signature.

• New version 1.1.0:

  • https://blog.clamav.net/2023/05/clamav-110-released.html
  • Added the ability to extract images embedded in HTML CSS

    <style> blocks.

  • Updated to Sigtool so that the '--vba' option will extract VBA code from Microsoft Office documents the same way that …

This update for clamav fixes the following issues:

New version 1.4.2:

• CVE-2025-20128, bsc#1236307: Fixed a possible buffer overflow read bug in the OLE2 file parser that could cause a denial-of-service (DoS) condition.

• Start clamonacc with --fdpass to avoid errors due to clamd not being able to access user files. (bsc#1232242)

• New version 1.4.1:

  • https://blog.clamav.net/2024/09/clamav-141-132-107-and-010312-security.html

• New version 1.4.0:

  • Added support for extracting ALZ archives.
  • Added support for extracting LHA/LZH archives.
  • 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.
  • https://blog.clamav.net/2024/08/clamav-140-feature-release-and-clamav.html

• New version 1.3.2:

  • 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.
  • CVE-2024-20505: Fixed a possible out-of-bounds read bug in the PDF file parser that could cause a denial-of-service condition.
  • 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.
  • Fixed an unaligned pointer dereference issue on select architectures.
  • Fixes to Jenkins CI pipeline.

• New Version: 1.3.1:

  • CVE-2024-20380: Fixed a possible crash in the HTML file parser that could cause a denial-of-service (DoS) condition.
  • Updated select Rust dependencies to the latest versions.
  • Fixed a bug causing some text to be truncated when converting from UTF-16.
  • Fixed assorted complaints identified by Coverity static analysis.
  • Fixed a bug causing CVDs downloaded by the DatabaseCustomURL
  • Added the new 'valhalla' database name to the list of optional databases in preparation for future work.

• New version: 1.3.0:

  • Added support for extracting and scanning attachments found in Microsoft OneNote section files. OneNote parsing will be enabled by default, but may be optionally disabled.
  • Added file type recognition for compiled Python ('.pyc') files.
  • Improved support for decrypting PDFs with empty passwords.
  • Fixed a warning when scanning some HTML files.
  • ClamOnAcc: Fixed an infinite loop when a watched directory does not exist.
  • ClamOnAcc: Fixed an infinite loop when a file has been deleted before a scan.

• New version: 1.2.0:

  • Added support for extracting Universal Disk Format (UDF) partitions.
  • Added an option to customize the size of ClamAV's clean file cache.
  • Raised the MaxScanSize limit so the total amount of data scanned when scanning a file or archive may exceed 4 gigabytes.
  • Added ability for Freshclam to use a client certificate PEM file and a private key PEM file for authentication to a private mirror.
  • Fix an issue extracting files from ISO9660 partitions where the files are listed in the plain ISO tree and there also exists an empty Joliet tree.
  • PID and socket are now located under /run/clamav/clamd.pid and /run/clamav/clamd.sock .
  • bsc#1211594: Fixed an issue where ClamAV does not abort the signature load process after partially loading an invalid signature.

• New version 1.1.0:

  • https://blog.clamav.net/2023/05/clamav-110-released.html
  • Added the ability to extract images embedded in HTML CSS

    <style> blocks.

  • Updated to Sigtool so that the '--vba' option will extract VBA code from Microsoft Office documents the same way that …

It was discovered that ClamAV incorrectly handled decrypting OLE2 content. A remote attacker could possibly use this issue to cause ClamAV to crash, resulting in a denial of service.