-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

===========================================================================
             AUSCERT External Security Bulletin Redistribution

                               ESB-2020.1012
       CVE-2020-10663: Unsafe Object Creation Vulnerability in JSON
                             (Additional fix)
                               20 March 2020

===========================================================================

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:           Ruby
Publisher:         Ruby
Operating System:  Windows
                   UNIX variants (UNIX, Linux, OSX)
Impact/Access:     Execute Arbitrary Code/Commands -- Remote/Unauthenticated
                   Denial of Service               -- Remote/Unauthenticated
Resolution:        Patch/Upgrade
CVE Names:         CVE-2020-10663 CVE-2013-0269 

Reference:         ASB-2013.0028
                   ESB-2013.1181
                   ESB-2013.0952

Original Bulletin: 
   https://www.ruby-lang.org/en/news/2020/03/19/json-dos-cve-2020-10663/

- --------------------------BEGIN INCLUDED TEXT--------------------

CVE-2020-10663: Unsafe Object Creation Vulnerability in JSON (Additional fix)

Posted by mame on 19 Mar 2020

There is an unsafe object creation vulnerability in the json gem bundled with
Ruby. This vulnerability has been assigned the CVE identifier CVE-2020-10663 .
We strongly recommend upgrading the json gem.

Details

When parsing certain JSON documents, the json gem (including the one bundled
with Ruby) can be coerced into creating arbitrary objects in the target system.

This is the same issue as CVE-2013-0269 . The previous fix was incomplete,
which addressed JSON.parse(user_input) , but didn  t address some other styles
of JSON parsing including JSON(user_input) and JSON.parse(user_input, nil) .

See CVE-2013-0269 in detail. Note that the issue was exploitable to cause a
Denial of Service by creating many garbage-uncollectable Symbol objects, but
this kind of attack is no longer valid because Symbol objects are now
garbage-collectable. However, creating arbitrary objects may cause severe
security consequences depending upon the application code.

Please update the json gem to version 2.3.0 or later. You can use gem update
json to update it. If you are using bundler, please add gem "json", ">= 2.3.0"
to your Gemfile .

Affected versions

  o JSON gem 2.2.0 or prior

Credits

Thanks to Jeremy Evans for discovering this issue.

History

  o Originally published at 2020-03-19 13:00:00 (UTC)

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.

NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

        https://www.auscert.org.au/bulletins/

===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072

Internet Email: auscert@auscert.org.au
Facsimile:      (07) 3365 7031
Telephone:      (07) 3365 4417 (International: +61 7 3365 4417)
                AusCERT personnel answer during Queensland business hours
                which are GMT+10:00 (AEST).
                On call after hours for member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967
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=rPcQ
-----END PGP SIGNATURE-----