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DBI-1.650
⭐ Starred 84 / DBD::File::Roadmap
Security Advisories (4)
CVE-2026-15043 (2026-07-14)

DBI::SQL::Nano versions from 1.42 before 1.651 for Perl have inverted <= and >= SQL operators on text. DBI::SQL::Nano, DBI's built-in mini-SQL engine, evaluated WHERE predicates incorrectly in some cases. In the non-numeric string branch of the is_matched method, <= was evaluated using Perl's ge operator, and >= was evaluated using Perl's le operator. SQL::Nano is the fallback query engine for DBI's file-backed drivers (DBD::File, DBD::DBM, CSV-style drivers) whenever SQL::Statement is not installed, and is forced whenever DBI_SQL_NANO=1. Queries over such tables use these predicates directly. The impact depends on the context. Where an application relies on a WHERE clause to filter file-backed data for policy or authorization, an inverted <=/>= comparison silently returns the wrong rows.

CVE-2026-15392 (2026-07-14)

DBD::File versions before 1.651 for Perl do not ensure the table file is not a symlink to an untrusted location. The complete_table_name method builds the absolute table file path without checking whether the file is a symbolic link. A link inside the data directory can point to a table file at any path outside of the configured f_dir and f_dir_search directories. Callers of file-based drivers can read or write files outside of the data directory.

CVE-2026-60081 (2026-07-14)

DBI::ProfileData versions before 1.651 for Perl do not limit the path index. The path index column of profile dump files is used to allocate an array of data for the parser. An unbounded value allows an attacker to specify a large index and consume available memory.

CVE-2026-60082 (2026-07-14)

DBI versions before 1.651 for Perl do not enforce statement handle consistency with the row. When the statement handle had no fields but the source row was non-empty, the internal row-buffer helper would read from a negative array index. This could be triggered by a caller supplying inconsistent metadata and rows to the prepare method.

NAME

DBD::File::Roadmap - Planned Enhancements for DBD::File and pure Perl DBD's

Jens Rehsack - May 2010

SYNOPSIS

This document gives a high level overview of the future of the DBD::File DBI driver and groundwork for pure Perl DBI drivers.

The planned enhancements cover features, testing, performance, reliability, extensibility and more.

CHANGES AND ENHANCEMENTS

Features

There are some features missing we would like to add, but there is no time plan:

LOCK TABLE

The newly implemented internal common table meta storage area would allow us to implement LOCK TABLE support based on file system flock () support.

Transaction support

While DBD::AnyData recommends explicitly committing by importing and exporting tables, DBD::File might be enhanced in a future version to allow transparent transactions using the temporary tables of SQL::Statement as shadow (dirty) tables.

Transaction support will heavily rely on lock table support.

Data Dictionary Persistence

SQL::Statement provides dictionary information when a "CREATE TABLE ..." statement is executed. This dictionary is preserved for some statement handle attribute fetches (as NULLABLE or PRECISION).

It is planned to extend DBD::File to support data dictionaries to work on the tables in it. It is not planned to support one table in different dictionaries, but you can have several dictionaries in one directory.

SQL Engine selecting on connect

Currently the SQL engine selected is chosen during the loading of the module DBI::SQL::Nano. Ideally end users should be able to select the engine used in DBI->connect () with a special DBD::File attribute.

Other points of view to the planned features (and more features for the SQL::Statement engine) are shown in SQL::Statement::Roadmap.

Testing

DBD::File and the dependent DBD::DBM requires a lot more automated tests covering API stability and compatibility with optional modules like SQL::Statement.

Performance

Several arguments for support of features like indexes on columns and cursors are made for DBD::CSV (which is a DBD::File based driver, too). Similar arguments could be made for DBD::DBM, DBD::AnyData, DBD::RAM or DBD::PO etc.

To improve the performance of the underlying SQL engines, a clean re-implementation seems to be required. Currently both engines are prematurely optimized and therefore it is not trivial to provide further optimization without the risk of breaking existing features.

Join the DBI developers IRC channel at irc://irc.perl.org/dbi to participate or post to the DBI Developers Mailing List.

Reliability

DBD::File currently lacks the following points:

duplicate table names

It is currently possible to access a table quoted with a relative path (a) and additionally using an absolute path (b). If (a) and (b) are the same file that is not recognized (except for flock protection handled by the Operating System) and two independent tables are handled.

invalid table names

The current implementation does not prevent someone choosing a directory name as a physical file name for the table to open.

Extensibility

I (Jens Rehsack) have some (partially for example only) DBD's in mind:

DBD::Sys

Derive DBD::Sys from a common code base shared with DBD::File which handles all the emulation DBI needs (as getinfo, SQL engine handling, ...)

DBD::Dir

Provide a DBD::File derived to work with fixed table definitions through the file system to demonstrate how DBI / Pure Perl DBDs could handle databases with hierarchical structures.

DBD::Join

Provide a DBI driver which is able to manage multiple connections to other Databases (as DBD::Multiplex), but allow them to point to different data sources and allow joins between the tables of them:

  # Example
  # Let table 'lsof' being a table in DBD::Sys giving a list of open files using lsof utility
  # Let table 'dir' being a atable from DBD::Dir
  $sth = $dbh->prepare( "select * from dir,lsof where path='/documents' and dir.entry = lsof.filename" )
  $sth->execute(); # gives all open files in '/documents'
  ...

  # Let table 'filesys' a DBD::Sys table of known file systems on current host
  # Let table 'applications' a table of your Configuration Management Database
  #  where current applications (relocatable, with mountpoints for filesystems)
  #  are stored
  $sth = dbh->prepare( "select * from applications,filesys where " .
                       "application.mountpoint = filesys.mountpoint and ".
		       "filesys.mounted is true" );
  $sth->execute(); # gives all currently mounted applications on this host

PRIORITIES

Our priorities are focused on current issues. Initially many new test cases for DBD::File and DBD::DBM should be added to the DBI test suite. After that some additional documentation on how to use the DBD::File API will be provided.

Any additional priorities will come later and can be modified by (paying) users.

RESOURCES AND CONTRIBUTIONS

See CONTRIBUTING.md for how you can help.

If your company has benefited from DBI, please consider if it could make a donation to The Perl Foundation "DBI Development" fund at http://dbi.perl.org/donate to secure future development.

Alternatively, if your company would benefit from a specific new DBI feature, please consider sponsoring it's development through the options listed in the section "Commercial Support from the Author" on http://dbi.perl.org/support/.

Using such targeted financing allows you to contribute to DBI development and rapidly get something specific and directly valuable to you in return.

My company also offers annual support contracts for the DBI, which provide another way to support the DBI and get something specific in return. Contact me for details.

Thank you.