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# TFTP Release Notes

## Tftp 1.2.4

### Fixed Bugs and Malfunctions

- An issue in the undocumented initial state option \[\{root_dir,Dir\}] to the tftp_file module has been fixed. The request file name was just concatenated to Dir so it was possible to traverse above Dir by using "../" file path components. Now the option actually restricts local file operations to the Dir directory and subdirectories.
  
  The initial state option and how to use it was previously undocumented, so it is unlikely that anyone would have used it without understanding its peculiarities.
  
  The documentation of the TFTP application has also been clarified to make it obvious that the default server configuration allows read and write access to all files that are readable or writable by the user running the Erlang VM, and that the default configuration therefore should be avoided.
  
  Thanks to Luigino Camastra at Aisle Research, for finding and reporting this issue.

  Own Id: OTP-19981 Aux Id: [PR-10706], [CVE-2026-21620]

[PR-10706]: https://github.com/erlang/otp/pull/10706
[CVE-2026-21620]: https://nvd.nist.gov/vuln/detail/2026-21620

## Tftp 1.2.3

### Improvements and New Features

- The license and copyright header has changed format to include an `SPDX-License-Identifier`. At the same time, most files have been updated to follow a uniform standard for license headers.

  Own Id: OTP-19575 Aux Id: [PR-9670]

[PR-9670]: https://github.com/erlang/otp/pull/9670

## Tftp 1.2.2.1

### Fixed Bugs and Malfunctions

- An issue in the undocumented initial state option \[\{root_dir,Dir\}] to the tftp_file module has been fixed. The request file name was just concatenated to Dir so it was possible to traverse above Dir by using "../" file path components. Now the option actually restricts local file operations to the Dir directory and subdirectories.
  
  The initial state option and how to use it was previously undocumented, so it is unlikely that anyone would have used it without understanding its peculiarities.
  
  The documentation of the TFTP application has also been clarified to make it obvious that the default server configuration allows read and write access to all files that are readable or writable by the user running the Erlang VM, and that the default configuration therefore should be avoided.
  
  Thanks to Luigino Camastra at Aisle Research, for finding and reporting this issue.

  Own Id: OTP-19981 Aux Id: [PR-10706], [CVE-2026-21620]

[PR-10706]: https://github.com/erlang/otp/pull/10706
[CVE-2026-21620]: https://nvd.nist.gov/vuln/detail/2026-21620

## Tftp 1.2.2

### Fixed Bugs and Malfunctions

- Fix specs in tftp:read_file function.

  Own Id: OTP-19446 Aux Id: [PR-9327], ERIERL-1179

[PR-9327]: https://github.com/erlang/otp/pull/9327

## Tftp 1.2.1

### Improvements and New Features

- The legacy dependency to `m:error_logger` has been removed. `m:logger` is now used.

  Own Id: OTP-19114

## Tftp 1.2

### Improvements and New Features

- There is a new [`tftp_logger`](`m:tftp_logger`) callback behavior module.

  Own Id: OTP-18787 Aux Id: [PR-7700]

- The documentation has been migrated to use Markdown and ExDoc.

  Own Id: OTP-18955 Aux Id: [PR-8026]

[PR-7700]: https://github.com/erlang/otp/pull/7700
[PR-8026]: https://github.com/erlang/otp/pull/8026

## Tftp 1.1.1.1

### Fixed Bugs and Malfunctions

* An issue in the undocumented initial state option \[\{root_dir,Dir\}] to the tftp_file module has been fixed. The request file name was just concatenated to Dir so it was possible to traverse above Dir by using "../" file path components. Now the option actually restricts local file operations to the Dir directory and subdirectories.

  The initial state option and how to use it was previously undocumented, so it is unlikely that anyone would have used it without understanding its peculiarities.

  The documentation of the TFTP application has also been clarified to make it obvious that the default server configuration allows read and write access to all files that are readable or writable by the user running the Erlang VM, and that the default configuration therefore should be avoided.

  Thanks to Luigino Camastra at Aisle Research, for finding and reporting this issue.

  Own Id: OTP-19981 Aux Id: PR-10706, CVE-2026-21620

## Tftp 1.1.1

### Fixed Bugs and Malfunctions

- Replaced unintentional Erlang Public License 1.1 headers in some files with
  the intended Apache License 2.0 header.

  Own Id: OTP-18815 Aux Id: PR-7780

## Tftp 1.1

### Improvements and New Features

- The implementation has been fixed to use `proc_lib:init_fail/2,3` where
  appropriate, instead of `proc_lib:init_ack/1,2`.

  \*** POTENTIAL INCOMPATIBILITY \***

  Own Id: OTP-18490 Aux Id: OTP-18471, GH-6339, PR-6843

## Tftp 1.0.4

### Improvements and New Features

- Replace size/1 with either tuple_size/1 or byte_size/1

  The [`size/1`](`size/1`) BIF is not optimized by the JIT, and its use can
  result in worse types for Dialyzer.

  When one knows that the value being tested must be a tuple,
  [`tuple_size/1`](`tuple_size/1`) should always be preferred.

  When one knows that the value being tested must be a binary,
  [`byte_size/1`](`byte_size/1`) should be preferred. However,
  [`byte_size/1`](`byte_size/1`) also accepts a bitstring (rounding up size to a
  whole number of bytes), so one must make sure that the call to `byte_size/` is
  preceded by a call to [`is_binary/1`](`is_binary/1`) to ensure that bitstrings
  are rejected. Note that the compiler removes redundant calls to
  [`is_binary/1`](`is_binary/1`), so if one is not sure whether previous code
  had made sure that the argument is a binary, it does not harm to add an
  [`is_binary/1`](`is_binary/1`) test immediately before the call to
  [`byte_size/1`](`byte_size/1`).

  Own Id: OTP-18432 Aux Id:
  GH-6672,PR-6793,PR-6784,PR-6787,PR-6785,PR-6682,PR-6800,PR-6797,PR-6798,PR-6799,PR-6796,PR-6813,PR-6671,PR-6673,PR-6684,PR-6694,GH-6677,PR-6696,PR-6670,PR-6674

## Tftp 1.0.3

### Fixed Bugs and Malfunctions

- Missing runtime dependencies has been added to this application.

  Own Id: OTP-17243 Aux Id: PR-4557

## Tftp 1.0.2

### Improvements and New Features

- Removed compiler warnings.

  Own Id: OTP-16317 Aux Id: OTP-16183

## Tftp 1.0.1

### Fixed Bugs and Malfunctions

- Improved documentation.

  Own Id: OTP-15190

## TFTP 1.0

### First released version

- Inets application was split into multiple smaller protocol specific
  applications. The TFTP application is a standalone TFTP client and server with
  the same functionality as TFTP in Inets.

  Own Id: OTP-14113
