Multiple vulnerabilities in Sun Calendar Express Web Server

Multiple vulnerabilities in Sun Calendar Express Web Server

Core Security - CoreLabs 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

The Sun alert for the XSS vulnerabilities is available at:
http://sunsolve.sun.com/search/document.do?assetkey=1-26-256228-1

The Sun alert for the DoS vulnerability is available at:
http://sunsolve.sun.com/search/document.do?assetkey=1-26-255008-1

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@test.com&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 /legacy/files/attachments/core_security_advisories.asc.