/ 
Apache-Session-1.94
/ Apache::Session::Flex
Security Advisories (3)
CVE-2013-10075 (2026-05-08)

Apache::Session versions through 1.94 for Perl re-creates deleted sessions. The session stores Apache::Session::Store::File and Apache::Session::Store::DB_File will create a session that does not exist. This can lead to sessions being revived, potentially with data that was to be deleted.

CVE-2025-40931 (2026-03-05)

Apache::Session::Generate::MD5 versions through 1.94 for Perl create insecure session id. Apache::Session::Generate::MD5 generates session ids insecurely. The default session id generator returns a MD5 hash seeded with the built-in rand() function, the epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage. Predicable session ids could allow an attacker to gain access to systems. Note that the libapache-session-perl package in some Debian-based Linux distributions may be patched to use Crypt::URandom.

CVE-2026-5081 (2026-05-06)

Apache::Session::Generate::ModUniqueId versions from 1.54 through 1.94 for Perl session ids are insecure. Apache::Session::Generate::ModUniqueId (added in version 1.54) uses the value of the UNIQUE_ID environment variable for the session id. The UNIQUE_ID variable is set by the Apache mod_unique_id plugin, which generates unique ids for the request. The id is based on the IPv4 address, the process id, the epoch time, a 16-bit counter and a thread index, with no obfuscation. The server IP is often available to the public, and if not available, can be guessed from previous session ids being issued. The process ids may also be guessed from previous session ids. The timestamp is easily guessed (and leaked in the HTTP Date response header). The purpose of mod_unique_id is to assign a unique id to requests so that events can be correlated in different logs. The id is not designed, nor is it suitable for security purposes.

NAME

Apache::Session::Flex - Specify everything at runtime

SYNOPSIS

use Apache::Session::Flex;

tie %hash, 'Apache::Session::Flex', $id, {
   Store     => 'DB_File',
   Lock      => 'Null',
   Generate  => 'MD5',
   Serialize => 'Storable'
};

# or

tie %hash, 'Apache::Session::Flex', $id, {
   Store     => 'Postgres',
   Lock      => 'Null',
   Generate  => 'MD5',
   Serialize => 'Base64'
};

# you decide!

DESCRIPTION

This module is an implementation of Apache::Session. Unlike other implementations, it allows you to specify the backing store, locking scheme, ID generator, and data serializer at runtime. You do this by passing arguments in the usual Apache::Session style (see SYNOPSIS). You may use any of the modules included in this distribution, or a module of your own making. If you wish to use a module of your own making, you should make sure that it is available under the Apache::Session package namespace.

USAGE

You pass the modules you want to use as arguments to the constructor. The Apache::Session::Whatever part is appended for you: you should not supply it. For example, if you wanted to use MySQL as the backing store, you should give the argument Store = 'MySQL'>, and not Store = 'Apache::Session::Store::MySQL'>. There are four modules that you need to specify. Store is the backing store to use. Lock is the locking scheme. Generate is the ID generation module. Serialize is the data serialization module.

There are many modules included in this distribution. For each role, they are:

Store:
   MySQL
   Postgres
   DB_File
   File

Lock:
   Null
   MySQL
   Semaphore

Generate:
   MD5

Serialize:
   Storable
   Base64
   UUEncode

In addition to the arguments needed by this module, you must provide whatever arguments are expected by the backing store and lock manager that you are using. Please see the documentation for those modules.

AUTHOR

This module was written by Jeffrey William Baker <jwbaker@acm.org>.

SEE ALSO

Apache::Session::File, Apache::Session::DB_File, Apache::Session::MySQL, Apache::Session::Postgres, Apache::Session