CORE-2009-0108: Multiple vulnerabilities in Sun Calendar Express Web Server

[CORE Security Technologies Advisories <advisories@xxxxxxxxxxxxxxxx>]

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      Core Security Technologies - CoreLabs Advisory
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   Multiple vulnerabilities in Sun Calendar Express Web Server


1. *Advisory Information*

Title: Multiple vulnerabilities in Sun Calendar Express Web Server
Advisory ID: CORE-2009-0108
Advisory URL: http://www.coresecurity.com/content/sun-calendar-express
Date published: 2009-03-31
Date of last update: 2009-03-31
Vendors contacted: Sun Microsystems
Release mode: Coordinated release


2. *Vulnerability Information*

Class: Denial of service (DoS), Cross site scripting (XSS)
Remotely Exploitable: Yes
Locally Exploitable: No
Bugtraq ID: 34150, 34152, 34153
CVE Name: N/A


3. *Vulnerability Description*

Several vulnerabilities have been discovered in Sun Java System Calendar
Express web server [1]. First, an attacker can crash the web server
creating a Denial of Service condition by simply requesting certain URL
twice. Second, several Cross-site scripting vulnerabilities [2], [3]
were found in the following files/urls:

   1. 'https://<server>:3443/login.wcap'
   2. 'https://<server>:3443/command.shtml'

 Cross-site scripting (XSS) vulnerabilities allow an attacker to execute
arbitrary scripting code in the context of the user browser (in the
vulnerable application's domain). For example, an attacker could exploit
an XSS vulnerability to steal user cookies (and then impersonate the
legitimate user) or fake a page requesting information to the user (i.e.
credentials). This vulnerability occurs when user-supplied data is
displayed without encoding.


4. *Vulnerable packages*

   . Sun ONE Calendar Server 6.0
   . Sun Java System Calendar Server 6 2004Q2
   . Sun Java System Calendar Server 6 2005Q1
   . Sun Java System Calendar Server 6 2005Q4
   . Sun Java System Calendar Server 6.3
   . Sun Java System Calendar Server 6.3-7.01 (built Feb 20 2008)


5. *Vendor Information, Solutions and Workarounds*

Sun has published patches and a Sun alert for these vulnerabilities. The
Sun alert will be available at:
http://sunsolve.sun.com/search/document.do?assetkey=1-26-256228-1


6. *Credits*

These vulnerabilities were discovered by the SCS team from Core Security
Technologies.


7. *Technical Description / Proof of Concept Code*

Cross-Site Scripting (commonly referred to as XSS) bugs arise from a web
application's improper encoding or filtering of input obtained from
untrusted sources. These bugs allow an attacker to inject malicious tags
and/or script code that is later executed in the context of a web
browser when the user accesses the vulnerable web site. The injected
code then takes advantage of the trust relationship between the web
browser and the vulnerable web application. Attacks that exploit XSS
bugs are targeted at users of a vulnerable web application rather than
at the application itself, although one could say that since the XSS
vulnerability in the web application created the vector that allows the
compromise of several of its user's web browsers, the web application
itself originated the problem. The term 'cross-site scripting' is also
sometimes used in a broader-sense referring to different types of
vulnerabilities that lead to attacks that inject scripting code into
client applications from sources that would not be trusted during script
execution runtime if the corresponding bug did not exist. For additional
information, please look at the references [2], [3], [4], [5] and [6].


7.1. *Vulnerability #1 - XSS (BID 34152)*

Cross-site scripting vulnerabilities were found in the following file/url:

/-----------
https://<server>:3443/login.wcap
- -----------/

 This is the login page of the Sun Java System Calendar Express Web
application; although the affected URL is originally accessed through a
POST request, this vulnerability can be exploited both with a GET and
with a POST request.

Using the following variables:

/-----------
Fmt-out
- -----------/

 the contents of the variables previously mentioned are not being
encoded at the time of using them in HTML output, therefore allowing an
attacker who controls their content to insert javascript code.

The following code is a proof of concept of this flaw:

/-----------
https://<server>:3443/login.wcap?calid=&calname=&date=&fmt-out=<script>alert(document.cookie)</script>&view=&locale=&tzid=&test=1229606492214&user=test&password=test
- -----------/

*Note:* Fields previously listed were verified for this type of issue.
Other fields on this or other pages for this application could be also
vulnerable to the same type of issue.


7.2. *Vulnerability #2 - XSS (BID 34153)*

Cross-site scripting vulnerabilities were found in the following file/url:

/-----------
https://<server>:3443/command.shtml
- -----------/

 Using the following variables:

/-----------
date
- -----------/

 the contents of the 'date' variable are not being encoded at the time
Of using them in HTML output, therefore allowing an attacker who
controls their content to insert javascript code.

The following code is a proof of concept of this flaw:

/-----------
https://<server>:3443//command.shtml?view=overview&id=HK8CjQOkmbY&date=20081217T200734%27;alert('xss');//Z&caliad=someid@xxxxxxxx&security=1
- -----------/

*Note:* Fields previously listed were verified for this type of issue.
Other fields on this or other pages for this application could be also
vulnerable to the same type of issue.


7.3. *Vulnerability #3 - DoS (BID 34150)*

An attacker can crash the Sun Java System Calendar Express web server
creating a Denial of Service condition by simply requesting certain URL
twice. Go to a browser and enter the following URL:

/-----------
https://<server>:3443/?tzid=crash
- -----------/

 where 'crash' can in fact be any string with alphabetic characters. The
first time you will receive an error. If at this point you access again
'https://<server>:3443/', the web server will still be operational.
Then, access again the URL 'https://<server>:3443/?tzid=crash' that will
crash the server again but this time the web server will stop responding
permanently until the administrator restarts the process.


8. *Report Timeline*

. 2009-01-09: Core Security Technologies notifies Sun Security
Coordination Team of the vulnerability, setting the estimated
publication date of the advisory to Feb 2nd. Technical details provided
in an encrypted document.
. 2009-01-09: The vendor acknowledges reception of the report and asks
Core to postpone publication of the security advisory in order to have
enough time to investigate and fix the bugs. Vendor requests GPG key of
Core's security Advisories team.
. 2009-01-12: Core agrees to postpone publication of the security
advisory but asks the vendor for a feedback of the vendor's engineering
team as soon as possible in order to coordinate the release date of
fixes and security advisories.
. 2009-01-21: Core asks Sun for an estimated date for the release of
patches and fixes.
. 2009-01-21: Sun Security Coordination Team notifies Core that the
vendor's engineering team is hoping to have patches released sometime
near the end of February or the beginning of March. The time-frame is
tentative due to the vendor's QA testing process that includes testing
of all patches which may include fixes to bugs unrelated to those
reported by Core. Sun will issue a Sun Alert associated to these bugs
and would like to coordinate its publication date with that of Core's
security advisory.
. 2009-02-06: Core re-schedules the advisory publication date to Feb
25th. Updated timeline sent to the vendor requesting confirmation that
patches will be released by then.
. 2009-02-09: Sun Security Coordination team acknowledges previous email
from Core and indicates it has requested confirmation from the
engineering team that they are on track for release by the end of February.
. 2009-02-10: Vendor asks Core for the exact version and patch level of
the tested Calendar Express Web server package and provides the URL to
the latest released patch
(http://sunsolve.sun.com/search/document.do?assetkey=1-21-121657-32-1)
. 2009-02-10: Core sends requested information (output of csversion
command) and indicates that the bugs were found on release packages with
no additional patches installed.
. 2009-02-11: Sun security coordination team acknowledges email from
Core and indicates that it will pass the information to the engineering
team.
. 2009-02-16: The vendor asks Core to delay the advisory publication
until the end of March, in order to finish a rigorous process of
internal testing. Sun also indicates that the DoS vulnerability had been
indentified previously as Sun bug 6728790 and fixed in patches already
released: Patches 121657-30 (Solaris SPARC), 121658-30 (Solaris x86) and
121659-30 (Linux) and also in the later revisions of these patches.
. 2009-02-16: Core re-schedules the advisory publication date to March
30th. Core indicates that it would appreciate further technical details
about the flaws from the vendors engineering team.
. 2009-02-17: Vendor acknowledges previous email.
. 2009-03-17: Core reminds the vendor that publication of the advisory
is scheduled for March 30th. Core also requests updated information
about the development and release of fixed versions.
. 2009-03-23: Vendor estimates that it is on track to have the fix ready
for publication at the end of the month, March 30th.
. 2009-03-23: Core acknowledges reception and requests a list of
affected versions and a link to fixed versions and any additional
information for Sun customers.
. 2009-03-25: Vendor informs that fixes will probably be released on
March 30th, and provides a list of affected products and versions.
. 2009-03-30: Core requests confirmation that patches will be released.
. 2009-03-31: Vendor confirms the release of patches and provides a link
to the Sun alert.
. 2009-03-31: The advisory CORE-2009-0108 is published.


9. *References*

[1] http://www.sun.com/software/products/calendar_srvr/
[2] HTML Code Injection and Cross-Site Scripting
http://www.technicalinfo.net/papers/CSS.html.
[3] The Cross-Site Scripting FAQ (XSS)
http://www.cgisecurity.com/articles/xss-faq.shtml
[4] How to prevent Cross-Site Scripting Security Issues
http://support.microsoft.com/default.aspx?scid=KB;en-us;q252985
[5] How to review ASP Code for CSSI Vulnerability
http://support.microsoft.com/default.aspx?scid=kb;EN-US;253119
[6] How to review Visual InterDev Generated Code for CSSI Vulnerability
http://support.microsoft.com/default.aspx?scid=kb;EN-US;253120


10. *About CoreLabs*

CoreLabs, the research center of Core Security Technologies, is charged
with anticipating the future needs and requirements for information
security technologies. We conduct our research in several important
areas of computer security including system vulnerabilities, cyber
attack planning and simulation, source code auditing, and cryptography.
Our results include problem formalization, identification of
vulnerabilities, novel solutions and prototypes for new technologies.
CoreLabs regularly publishes security advisories, technical papers,
project information and shared software tools for public use at:
http://www.coresecurity.com/corelabs.


11. *About Core Security Technologies*

Core Security Technologies develops strategic solutions that help
security-conscious organizations worldwide develop and maintain a
proactive process for securing their networks. The company's flagship
product, CORE IMPACT, is the most comprehensive product for performing
enterprise security assurance testing. CORE IMPACT evaluates network,
endpoint and end-user vulnerabilities and identifies what resources are
exposed. It enables organizations to determine if current security
investments are detecting and preventing attacks. Core Security
Technologies augments its leading technology solution with world-class
security consulting services, including penetration testing and software
security auditing. Based in Boston, MA and Buenos Aires, Argentina, Core
Security Technologies can be reached at 617-399-6980 or on the Web at
http://www.coresecurity.com.


12. *Disclaimer*

The contents of this advisory are copyright (c) 2009 Core Security
Technologies and (c) 2009 CoreLabs, and may be distributed freely
provided that no fee is charged for this distribution and proper credit
is given.


13. *PGP/GPG Keys*

This advisory has been signed with the GPG key of Core Security
Technologies advisories team, which is available for download at
http://www.coresecurity.com/files/attachments/core_security_advisories.asc.

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