Getting started¶
YARA is a multi-platform program running on Windows, Linux and Mac OS X. You can find the latest release at https://github.com/VirusTotal/yara/releases.
Compiling and installing YARA¶
Download the source tarball and get prepared for compiling it:
tar -zxf yara-4.4.0.tar.gz
cd yara-4.4.0
./bootstrap.sh
Make sure you have automake
, libtool
, make
and gcc
and pkg-config
installed in your system. Ubuntu and Debian users can use:
sudo apt-get install automake libtool make gcc pkg-config
If you plan to modify YARA's source code you may also need flex
and
bison
for generating lexers and parsers:
sudo apt-get install flex bison
Compile and install YARA in the standard way:
./bootstrap.sh
./configure
make
sudo make install
Run the test cases to make sure that everything is fine:
make check
Some of YARA's features depend on the OpenSSL library. Those features are
enabled only if you have the OpenSSL library installed in your system. If not,
YARA is going to work fine but you won't be able to use the disabled features.
The configure
script will automatically detect if OpenSSL is installed or
not. If you want to enforce the OpenSSL-dependent features you must pass
--with-crypto
to the configure
script. Ubuntu and Debian users can use
sudo apt-get install libssl-dev
to install the OpenSSL library.
The following modules are not compiled into YARA by default:
- cuckoo
- magic
- dotnet
If you plan to use them you must pass the corresponding --enable-<module
name>
arguments to the configure
script.
For example:
./configure --enable-cuckoo
./configure --enable-magic
./configure --enable-dotnet
./configure --enable-cuckoo --enable-magic --enable-dotnet
Modules usually depend on external libraries, depending on the modules you choose to install you'll need the following libraries:
- cuckoo:
- Depends on Jansson for parsing JSON.
Some Ubuntu and Debian versions already include a package named
libjansson-dev
, ifsudo apt-get install libjansson-dev
doesn't work for you then get the source code from its repository.
Installing with vcpkg¶
You can also download and install YARA using the vcpkg dependency manager:
git clone https://github.com/microsoft/vcpkg.git
cd vcpkg
./bootstrap-vcpkg.sh
./vcpkg integrate install
vcpkg install yara
The YARA port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please create an issue or pull request on the vcpkg repository.
Installing on Windows¶
Compiled binaries for Windows in both 32 and 64 bit flavors can be found in the
link below. Just download the version you want, unzip the archive, and put the
yara.exe
and yarac.exe
binaries anywhere in your disk.
To install YARA using Scoop or Chocolatey, simply type
scoop install yara
or choco install yara
. The integration with both Scoop and Chocolatey are
not maintained their respective teams, not by the YARA authors.
Installing on Mac OS X with Homebrew¶
To install YARA using Homebrew, simply type
brew install yara
.
Installing yara-python
¶
If you plan to use YARA from your Python scripts you need to install the
yara-python
extension. Please refer to https://github.com/VirusTotal/yara-python
for instructions on how to install it.
Running YARA for the first time¶
Now that you have installed YARA you can write a very simple rule and use the command-line tool to scan some file:
echo "rule dummy { condition: true }" > my_first_rule
yara my_first_rule my_first_rule
Don't get confused by the repeated my_first_rule
in the arguments to
yara
, I'm just passing the same file as both the rules and the file to
be scanned. You can pass any file you want to be scanned (second argument).
If everything goes fine you should get the following output:
dummy my_first_rule
Which means that the file my_first_rule
is matching the rule named dummy
.
If you get an error like this:
yara: error while loading shared libraries: libyara.so.2: cannot open shared
object file: No such file or directory
It means that the loader is not finding the libyara
library which is
located in /usr/local/lib
. In some Linux flavors the loader doesn't look for
libraries in this path by default, we must instruct it to do so by adding
/usr/local/lib
to the loader configuration file /etc/ld.so.conf
:
sudo sh -c 'echo "/usr/local/lib" >> /etc/ld.so.conf'
sudo ldconfig
On newer Ubuntu releases such as 22.04 LTS, the correct loader configuration is
installed via dependencies to /etc/ld.so.conf.d/libc.conf
. In this case, the
following command alone is sufficient to configure the dynamic linker run-time
bindings.
sudo ldconfig
If you're using Windows PowerShell as your command shell, yara my_first_rule my_first_rule
may return this error:
my_first_rule(1): error: non-ascii character
You can avoid this by using the Set-Content
cmdlet to specify ascii output when creating your rule file:
Set-Content -path .\my_first_rule -Value "rule dummy { condition: true }" -Encoding Ascii
.\yara my_first_rule my_first_rule