ClamAV is an open source antivirus toolkit designed to detect viruses, trojans, malware, and other malicious threats. The project was originally created by Tomasz Kojm and is now maintained by Cisco Talos.
The software was first released in 2002 and is available under the GNU General Public License. It supports multiple operating systems including Linux, Windows, and macOS.
ClamAV is particularly known for its use in mail gateway scanning, where it scans email attachments for malware before they reach users.
Download ClamAV 1.5.3 - Software Mirrors |
|---|
Download ClamAV 1.5.3 for Windows |
Download ClamAV 1.5.3 for macOS |
Download ClamAV 1.5.3 for Linux |
ClamAV 1.5.3 Release Notes: ClamAV 1.5.3 is a patch release with the following fixes: - [CVE-2026-20217](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20217): Fixed a bug in the PESpin unpacker cleanup path that could free pointers into the scanned file buffer and crash the scanner. This issue affects ClamAV 1.5.2, 1.4.4, and all prior versions as far back as 2005. The fix is included in 1.5.3 and 1.4.5. Thank you to Atuin - Automated Vulnerability Discovery Engine, Tianchu Chen of Tencent Xuanwu Lab for identifying this issue. - [CVE-2026-20213](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20213): Fixed an integer overflow in PE rebuild size calculations that could be reached through a malformed Aspack-packed PE file and lead to a heap buffer overflow write. This issue affects ClamAV 1.5.2, 1.4.4, and all prior versions as far back as 2007. The fix is included in 1.5.3 and 1.4.5. Thank you to Trail of Bits, in collaboration with Anthropic, for identifying this issue. - [CVE-2026-20216](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20216): Fixed an InstallShield archive extraction limit bypass that could write far more temporary data than intended and exhaust temporary storage. This issue affects ClamAV 1.5.2, 1.4.4, and all prior versions as far back as 2009. The fix is included in 1.5.3 and 1.4.5. Thank you to Mizu for identifying this issue. - [CVE-2026-20214](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20214): Fixed an FSG unpacker loop underflow that could write past the section array while scanning a malformed PE file. This issue affects ClamAV 1.5.2, 1.4.4, and all prior versions as far back as 2004. The fix is included in 1.5.3 and 1.4.5. Thank you to Trail of Bits, in collaboration with Anthropic, for identifying this issue. - [CVE-2026-20243](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20243): Fixed ALZ parser size handling bugs that could cause malformed ALZ archives to panic, abort the scanner, or skip expected scan-limit handling. This issue affects ClamAV 1.5.0 through 1.5.2 and 1.4.0 through 1.4.4. The fix is included in 1.5.3 and 1.4.5. Thank you to Yazdan Soltani for identifying this issue. - [CVE-2026-20215](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20215): Fixed a 7z parser substream count overflow that could under-allocate parser metadata arrays and write past them while reading a malformed archive. This issue affects ClamAV 1.5.2, 1.4.4, and all prior versions back to 2009. The fix is included in 1.5.3 and 1.4.5. Thank you to Trail of Bits, in collaboration with Anthropic, for identifying this issue. - [CVE-2026-20244](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-20244): Fixed 32-bit DMG parser size checks that could let a short mish stripe table pass validation and crash 32-bit scanner builds. This issue affects 32-bit ClamAV builds from 0.98.1 through 1.5.2, including 1.4.0 through 1.4.4 and 1.5.0 through 1.5.2. It does not affect 64-bit builds. The fix is included in 1.5.3 and 1.4.5. Thank you to Stanley John Tobias for identifying this issue. - Hardened `clamscan`, `clamdscan`, and `clamonacc` quarantine actions against time-of-check/time-of-use races that could redirect copied, moved, or removed files under unsafe quarantine directory configurations. Thank you to Hiroki Imai from Ricerca Security, Inc. for identifying this issue. - Upgraded the Rust `tar` dependency to resolve the RUSTSEC-2026-0067 and RUSTSEC-2026-0068 advisories, and upgraded the Rust `openssl` dependency to resolve CVE-2026-41676. - Raised the minimum required CMake version to 3.17 to fix Linux builds with libcurl v8.21.0 when linking static library dependencies. - Metadata preclass scans now run before the final scan verdict. - ClamOnAcc: Fixed errors when recursively excluded paths are children of an included path. - ClamOnAcc: Fixed hash bucket list corruption when two watched paths collide in the same bucket. These fixes are courtesy of sharkautarch. |
Key Features of ClamAV
Open Source Antivirus Engine
ClamAV is completely open source, allowing organizations and developers to inspect the code, customize detection rules, and integrate it into security systems.
This transparency makes it popular in enterprise environments and Linux based infrastructures.
Command Line Scanner
ClamAV primarily operates through command line tools such as:
clamscan for manual file scanning
clamdscan for faster daemon based scanning
freshclam for updating virus definitions
These tools allow administrators to automate malware scanning across servers and systems.
Automatic Virus Database Updates
ClamAV regularly updates its malware signature database. The update utility downloads the latest virus definitions several times per day to keep detection up to date.
Frequent updates help maintain protection against new malware threats.
Archive and File Format Scanning
The engine supports scanning of many file formats and archives, including:
ZIP, RAR, TAR, GZIP
Microsoft Office files
PDF documents
HTML and RTF files
It can also unpack nested archives to detect malware hidden inside compressed files.
Email and Gateway Protection
One of ClamAV’s main use cases is scanning email attachments. It integrates with mail servers and filters to block infected files before they reach users.
Because of this capability, it has become a standard antivirus engine for many email gateways and hosting environments.
Performance and Usability
ClamAV is optimized for server environments where large volumes of files must be scanned quickly. Its architecture includes a multi threaded daemon that can process multiple scanning requests simultaneously.
Because the software is command line based, it may require technical knowledge to configure and operate effectively. Many administrators integrate it with scripts, web servers, or mail systems for automated scanning.
Graphical interfaces such as ClamTk exist but are developed by third parties.
Pros and Cons
Advantages
Completely open source and free
Strong integration with Linux servers
Frequently updated malware database
Supports many file formats and archives
Effective for email and server malware scanning
Limitations
Command line interface can be difficult for beginners
Detection rates may be lower than some commercial antivirus solutions in certain tests
Limited real time desktop protection compared to full endpoint security suites
ClamAV is often used as part of a broader security setup rather than as a standalone desktop antivirus.
Who Should Use ClamAV
ClamAV is best suited for:
Linux server administrators
Email server operators
Web hosting providers
Security professionals managing file uploads
Organizations needing open source antivirus solutions
It is commonly used in hosting environments, web servers, and email filtering systems.
Final Verdict
ClamAV is a powerful open source antivirus engine widely used for server side malware detection and email security. With a regularly updated signature database, support for many file formats, and strong integration capabilities, it remains a reliable tool for protecting systems from malware.
While it may not replace full desktop antivirus software, ClamAV continues to be an essential security component for many Linux servers and enterprise infrastructures.
ClamAV is one of the most widely used open source antivirus engines, especially in server environments and email security systems. It is commonly used on Linux servers, mail gateways, and file servers to detect malware and other malicious threats.
Developer:
ClamAV Team
Operating System:
Windows / macOS / Linux
Date Added:
2026-07-02T07:01:13.623Z
Categories:
Post a Comment/Report Broken Link: