sympa -- Inappropriate use of the cookie parameter can be a security threat. This parameter may also not provide sufficient security.

Earlier versions of Sympa require a parameter named cookie in sympa.conf configuration file.

This parameter was used to make some identifiers generated by the system unpredictable. For example, it was used as following:

• To be used as a salt to encrypt passwords stored in the database by the RC4 symmetric key algorithm.

  Note that RC4 is no longer considered secure enough and is not supported in the current version of Sympa.

• To prevent attackers from sending crafted messages to achieve XSS and so on in message archives.

There were the following problems with the use of this parameter.

1. This parameter, for its purpose, should be different for each installation, and once set, it cannot be changed. As a result, some sites have been operating without setting this parameter. This completely invalidates the security measures described above.
2. Even if this parameter is properly set, it may be considered not being strong enough against brute force attacks.

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