clamd.conf(5)

NAME

clamd.conf - Configuration file for Clam AntiVirus Daemon

DESCRIPTION

clamd.conf configures the Clam AntiVirus daemon, clamd(8).

FILE FORMAT
The file consists of comments and options with arguments. Each line which starts with a hash (#) symbol is ignored by the parser. Options and arguments are case sensitive and of the form Option Argument. The arguments are of the following types:

BOOL
    Boolean value (yes/no or true/false or 1/0).

STRING
    String without blank characters.

SIZE
    Size in bytes. You can use 'M' or 'm' modifiers for megabytes and 'K' or 'k' for kilobytes.

NUMBER
    Unsigned integer.

DIRECTIVES

When some option is not used (commented out or not included in the configuration file at all) clamd takes a default action.

Example
    If this option is set clamd will not run.

LogFile STRING
    Enable logging to selected file.
    Default: no

LogFileUnlock BOOL
    Disable a system lock that protects against running clamd with the same configuration file multiple times.
    Default: no

LogFileMaxSize SIZE
    Limit the size of the log file. The logger will be automatically disabled if the file is greater than SIZE. Value of 0 disables the limit.
    Default: 1M

LogTime BOOL
    Log time for each message.
    Default: no

LogClean BOOL
    Log clean files.
    Default: no

LogSyslog BOOL
    Use system logger (can work together with LogFile).
    Default: no

LogFacility STRING
    Specify the type of syslog messages - please refer to 'man syslog' for facility names.
    Default: LOG_LOCAL6

LogVerbose BOOL
    Enable verbose logging.
    Default: no

PidFile STRING
    Save the process identifier of a listening daemon (main thread) to a specified file.
    Default: no

TemporaryDirectory STRING
    Optional path to the global temporary directory.
    Default: system specific (usually /tmp or /var/tmp).

DatabaseDirectory STRING
    Path to a directory containing database files.

OfficialDatabaseOnly BOOL
    Only load the official signatures published by the ClamAV project.
    Default: no

LocalSocket STRING
    Path to a local (Unix) socket the daemon will listen on.
    Default: no

LocalSocketGroup STRING
    Sets the group ownership on the unix socket.
    Default: the primary group of the user running clamd

LocalSocketMode STRING
    Sets the permissions on the unix socket to the specified mode.
    Default: socket is world readable and writable

FixStaleSocket BOOL
    Remove stale socket after unclean shutdown.
    Default: yes

TCPSocket NUMBER
    TCP port number the daemon will listen on.
    Default: no

TCPAddr STRING
    TCP socket address to bind to. By default clamd binds to INADDR_ANY.
    Default: no

MaxConnectionQueueLength NUMBER
    Maximum length the queue of pending connections may grow to.
    Default: 15

MaxThreads NUMBER
    Maximum number of threads running at the same time.
    Default: 10

ReadTimeout NUMBER
    Waiting for data from a client socket will timeout after this time (seconds).
    Default: 120

CommandReadTimeout NUMBER
    This option specifies the time (in seconds) after which clamd should timeout if a client doesn't provide any initial command after connecting. Note: the timeout for subsequents commands, and/or data chunks is specified by ReadTimeout.
    Default: 5

SendBufTimeout NUMBER
    This option specifies how long to wait (in milliseconds) if the send buffer is full. Keep this value low to prevent clamd hanging.
    Default: 500

MaxQueue NUMBER
    Maximum number of queued items (including those being processed by MaxThreads threads). It is recommended to have this value at least twice MaxThreads if possible.
    WARNING: you shouldn't increase this too much to avoid running out of file descriptors, the following condition should hold: MaxThreads*MaxRecursion + MaxQueue - MaxThreads + 6 < RLIMIT_NOFILE. RLIMIT_NOFILE is the maximum number of open file descriptors (usually 1024), set by ulimit -n.
    Default: 100

IdleTimeout NUMBER
    Waiting for a new job will timeout after this time (seconds).
    Default: 30

ExcludePath REGEX
    Don't scan files and directories matching REGEX. This directive can be used multiple times.
    Default: scan all

MaxDirectoryRecursion NUMBER
    Maximum depth directories are scanned at.
    Default: 15

FollowDirectorySymlinks BOOL
    Follow directory symlinks.
    Default: no

CrossFilesystems BOOL
    Scan files and directories on other filesystems.
    Default: yes

FollowFileSymlinks BOOL
    Follow regular file symlinks.
    Default: no

SelfCheck NUMBER
    Perform a database check.
    Default: 1800

VirusEvent COMMAND
    Execute COMMAND when a virus is found. In the command string %v will be replaced with the virus name.
    Default: no

ExitOnOOM BOOL
    Stop daemon when libclamav reports out of memory condition.
    Default: no

User STRING
    Run as another user (clamd must be started by root to make this option working).
    Default: no

AllowSupplementaryGroups BOOL
    Initialize supplementary group access (clamd must be started by root).
    Default: no

Foreground BOOL
    Don't fork into background.
    Default: no

Debug BOOL
    Enable debug messages from libclamav.

LeaveTemporaryFiles BOOL
    Do not remove temporary files (for debug purpose).
    Default: no

StreamMaxLength SIZE
    Clamd uses FTP-like protocol to receive data from remote clients. If you are using clamav-milter to balance load between remote clamd daemons on firewall servers you may need to tune the Stream* options. This option allows you to specify the upper limit for data size that will be transfered to remote daemon when scanning a single file. It should match your MTA's limit for a maximum attachment size.
    Default: 10M

StreamMinPort NUMBER
    Limit data port range.
    Default: 1024

StreamMaxPort NUMBER
    Limit data port range.
    Default: 2048

Bytecode BOOL
    With this option enabled ClamAV will load bytecode from the database. It is highly recommended you keep this option turned on, otherwise you may miss detections for many new viruses.
    Default: yes

BytecodeSecurity STRING
    Set bytecode security level. Possible values: None: no security at all, meant for debugging. DO NOT USE THIS ON PRODUCTION SYSTEMS, TrustSigned: trust bytecode loaded from signed .c[lv]d files and insert runtime safety checks for bytecode loaded from other sources, Paranoid: don't trust any bytecode, insert runtime checks for all. The recommended setting is TrustSigned, because bytecode in .cvd files already has safety checks inserted into it.
    Default: TrustSigned

BytecodeTimeout NUMBER
    Set bytecode timeout in milliseconds.
    Default: 60000

DetectPUA BOOL
    Detect Possibly Unwanted Applications.
    Default: No

ExcludePUA CATEGORY
    Exclude a specific PUA category. This directive can be used multiple times. See http://www.clamav.net/support/pua for the complete list of PUA categories.
    Default: Load all categories (if DetectPUA is activated)

IncludePUA CATEGORY
    Only include a specific PUA category. This directive can be used multiple times. See http://www.clamav.net/support/pua for the complete list of PUA categories.
    Default: Load all categories (if DetectPUA is activated)

AlgorithmicDetection BOOL
    In some cases (eg. complex malware, exploits in graphic files, and others), ClamAV uses special algorithms to provide accurate detection. This option controls the algorithmic detection.
    Default: yes

ScanPE BOOL
    PE stands for Portable Executable - it's an executable file format used in all 32 and 64-bit versions of Windows operating systems. This option allows ClamAV to perform a deeper analysis of executable files and it's also required for decompression of popular executable packers such as UPX.
    Default: yes

ScanELF BOOL
    Executable and Linking Format is a standard format for UN*X executables. This option allows you to control the scanning of ELF files.
    Default: yes

DetectBrokenExecutables BOOL
    With this option clamd will try to detect broken executables (both PE and ELF) and mark them as Broken.Executable.
    Default: no

ScanOLE2 BOOL
    This option enables scanning of OLE2 files, such as Microsoft Office documents and .msi files.
    Default: yes

ScanPDF BOOL
    This option enables scanning within PDF files.
    Default: yes

ScanHTML BOOL
    Enables HTML detection and normalisation.
    Default: yes

ScanMail BOOL
    Enable scanning of mail files.
    Default: yes

ScanPartialMessages BOOL
    Scan RFC1341 messages split over many emails. You will need to periodically clean up $TemporaryDirectory/clamav-partial directory. WARNING: This option may open your system to a DoS attack. Never use it on loaded servers.
    Default: no

MailMaxRecursion NUMBER (OBSOLETE)
    WARNING: This option is no longer accepted. See MaxRecursion.

PhishingSignatures BOOL
    With this option enabled ClamAV will try to detect phishing attempts by using signatures.
    Default: yes

PhishingScanURLs BOOL
    Scan URLs found in mails for phishing attempts using heuristics. This will classify "Possibly Unwanted" phishing emails as Phishing.Heuristics.Email.*
    Default: yes

PhishingAlwaysBlockSSLMismatch BOOL
    Always block SSL mismatches in URLs, even if the URL isn't in the database. This can lead to false positives.
    Default: no

PhishingAlwaysBlockCloak BOOL
    Always block cloaked URLs, even if URL isn't in database. This can lead to false positives.
    Default: no

HeuristicScanPrecedence BOOL
    Allow heuristic match to take precedence. When enabled, if a heuristic scan (such as phishingScan) detects a possible virus/phishing it will stop scanning immediately. Recommended, saves CPU scan-time. When disabled, virus/phishing detected by heuristic scans will be reported only at the end of a scan. If an archive contains both a heuristically detected virus/phishing, and a real malware, the real malware will be reported. Keep this disabled if you intend to handle "*.Heuristics.*" viruses differently from "real" malware. If a non-heuristically-detected virus (signature-based) is found first, the scan is interrupted immediately, regardless of this config option.
    Default: no

StructuredDataDetection BOOL
    Enable the DLP module.
    Default: no

StructuredMinCreditCardCount NUMBER
    This option sets the lowest number of Credit Card numbers found in a file to generate a detect.
    Default: 3

StructuredMinSSNCount NUMBER
    This option sets the lowest number of Social Security Numbers found in a file to generate a detect.
    Default: 3

StructuredSSNFormatNormal BOOL
    With this option enabled the DLP module will search for valid SSNs formatted as xxx-yy-zzzz.
    Default: Yes

StructuredSSNFormatStripped BOOL
    With this option enabled the DLP module will search for valid SSNs formatted as xxxyyzzzz.
    Default: No

ScanArchive BOOL
    Enable archive scanning.
    Default: yes

ArchiveMaxFileSize (OBSOLETE)
    WARNING: This option is no longer accepted. See MaxFileSize and MaxScanSize.

ArchiveMaxRecursion (OBSOLETE)
    WARNING: This option is no longer accepted. See MaxRecursion.

ArchiveMaxFiles (OBSOLETE)
    WARNING: This option is no longer accepted. See MaxFiles.

ArchiveMaxCompressionRatio (OBSOLETE)
    WARNING: This option is no longer accepted.

ArchiveBlockMax (OBSOLETE)
    WARNING: This option is no longer accepted.

ArchiveLimitMemoryUsage BOOL
    Use slower decompression algorithm which uses less memory. This option only affects the bzip2 decompressor.
    Default: no

ArchiveBlockEncrypted BOOL
    Mark encrypted archives as viruses (Encrypted.Zip, Encrypted.RAR).
    Default: no

MaxScanSize SIZE
    Sets the maximum amount of data to be scanned for each input file. Archives and other containers are recursively extracted and scanned up to this value. Warning: disabling this limit or setting it too high may result in severe damage to the system.
    Default: 100M

MaxFileSize SIZE
    Files larger than this limit won't be scanned. Affects the input file itself as well as files contained inside it (when the input file is an archive, a document or some other kind of container). Warning: disabling this limit or setting it too high may result in severe damage to the system.
    Default: 25M

MaxRecursion NUMBER
    Nested archives are scanned recursively, e.g. if a Zip archive contains a RAR file, all files within it will also be scanned. This options specifies how deeply the process should be continued. Warning: disabling this limit or setting it too high may result in severe damage to the system.
    Default: 16

MaxFiles NUMBER
    Number of files to be scanned within an archive, a document, or any other kind of container. Warning: disabling this limit or setting it too high may result in severe damage to the system.
    Default: 10000

ClamukoScanOnAccess BOOL
    Enable Clamuko. Dazuko (/dev/dazuko) must be configured and running.
    Default: no

ClamukoScannerCount NUMBER
    The number of scanner threads that will be started (DazukoFS only). Having multiple scanner threads allows Clamuko to serve multiple processes simultaneously. This is particularly beneficial on SMP machines.
    Default: 3

ClamukoScanOnOpen BOOL
    Scan files on open.
    Default: no

ClamukoScanOnClose BOOL
    Scan files on close.
    Default: no.

ClamukoScanOnExec BOOL
    Scan files on execute.
    Default: no

ClamukoIncludePath STRING
    Set the include paths (all files and directories inside them will be scanned). You can have multiple ClamukoIncludePath directives but each directory must be added in a separate line).
    Default: no

ClamukoExcludePath STRING
    Set the exclude paths. All subdirectories will also be excluded.
    Default: no

ClamukoMaxFileSize SIZE
    Ignore files larger than SIZE.
    Default: 5M

NOTES

All options expressing a size are limited to max 4GB. Values in excess will be resetted to the maximum.

FILES

/etc/clamd.conf

AUTHOR

Tomasz Kojm <tkojm@clamav.net>

SEE ALSO

clamd(8), clamdscan(1), clamav-milter(8), clamscan(1), freshclam(1), sigtool(1)