Koha 20.05.15 released, ⚠ security release

The Koha community is proud to announce the release of version 20.05.15.

As always you can download the release from:

Thank you very much to everyone involved in this release.

Please continue reading for the details this release.

Koha is the first free and open source software library automation
package (ILS). Development is sponsored by libraries of varying types
and sizes, volunteers, and support companies from around the world. The
website for the Koha project is:

Installation instructions can be found at:

  • Koha Wiki
  • OR in the INSTALL files that come in the tarball

Koha 20.05.15 is a bugfix/maintenance release with security fixes.

It includes 1 security fixes, 7 bugfixes.

System requirements

You can learn about the system components (like OS and database) needed for running Koha here: https://wiki.koha-community.org/wiki/System_requirements_and_recommendations

Security bugs


  • [28784] DoS in opac-search.pl causes OOM situation and 100% CPU (doesn’t require login!)

Critical bugs fixed

Hold requests

  • [28057] Confusion of biblionumber and biblioitemnumber in request.pl


  • [28462] TT tag on several lines break the translator tool


  • [28675] QOTD broken in 20.11 and below

Other bugs fixed

Hold requests

  • [28644] Can’t call method “borrowernumber” on an undefined value at C4/Reserves.pm line 607


  • [28518] “Return to the last advanced search” exclude keywords if more than 3


  • [28604] Bad encoding when using marc-in-json
  • [28632] patrons.t fragile on slow boxes


The Koha manual is maintained in Sphinx. The home page for Koha
documentation is

As of the date of these release notes, the Koha manual is available in the following languages:

The Git repository for the Koha manual can be found at


Complete or near-complete translations of the OPAC and staff
interface are available in this release for the following languages:

  • Arabic (98.2%)
  • Armenian (100%)
  • Armenian (Classical) (99.7%)
  • Chinese (Taiwan) (93.9%)
  • Czech (80.6%)
  • English (New Zealand) (66.6%)
  • English (USA)
  • Finnish (70.3%)
  • French (86.6%)
  • French (Canada) (96.9%)
  • German (100%)
  • German (Switzerland) (74.3%)
  • Greek (62.4%)
  • Hindi (100%)
  • Italian (100%)
  • Norwegian Bokmål (70.9%)
  • Polish (79.4%)
  • Portuguese (87.8%)
  • Portuguese (Brazil) (97.6%)
  • Russian (86.1%)
  • Slovak (89.3%)
  • Spanish (99.6%)
  • Swedish (79.2%)
  • Telugu (100%)
  • Turkish (100%)
  • Ukrainian (66.1%)

Partial translations are available for various other languages.

The Koha team welcomes additional translations; please see

For information about translating Koha, and join the koha-translate
list to volunteer:

The most up-to-date translations can be found at:

Release Team

The release team for Koha 20.05.15 is

  • Release Manager:


We thank the following individuals who contributed patches to Koha 20.05.15

  • Tomás Cohen Arazi (2)
  • Nick Clemens (3)
  • Jonathan Druart (6)
  • Victor Grousset (2)
  • Marcel de Rooy (2)
  • Koha translators (1)

We thank the following libraries, companies, and other institutions who contributed
patches to Koha 20.05.15

  • ByWater-Solutions (3)
  • Koha Community Developers (8)
  • Rijks Museum (2)
  • Theke Solutions (2)

We also especially thank the following individuals who tested patches
for Koha

  • Tomás Cohen Arazi (2)
  • Nick Clemens (3)
  • Jonathan Druart (5)
  • Katrin Fischer (3)
  • Lucas Gass (2)
  • Victor Grousset (16)
  • Kyle M Hall (9)
  • Joonas Kylmälä (2)
  • Owen Leonard (2)
  • David Nind (1)
  • Martin Renvoize (2)
  • Marcel de Rooy (2)
  • Fridolin Somers (9)
  • Petro Vashchuk (1)

We regret any omissions. If a contributor has been inadvertently missed,
please send a patch against these release notes to koha-devel@lists.koha-community.org.

Revision control notes

The Koha project uses Git for version control. The current development
version of Koha can be retrieved by checking out the master branch of:

The branch for this version of Koha and future bugfixes in this release
line is 20.05.x.

Bugs and feature requests

Bug reports and feature requests can be filed at the Koha bug
tracker at:

He rau ringa e oti ai.
(Many hands finish the work)

Autogenerated release notes updated last on 24 Aug 2021 19:32:02.