Epicor Retail Store Help System 3.2.03.01.008 Code Execution

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Title: Code Injection in Epicor Retail Store Help System  
CVE: CVE-2015-2210  
Vendor: Epicor  
Product: CRS Retail Store v3.2.03.01.008   
Affected version: 3.2.03.01.008  
Reported by: Zeng Xianbo Joseph ([email protected])  
Issue identified by: Zeng Xianbo Joseph and Alshi Shantanu   
  
OVERVIEW  
By design, the POS software requires a higher privileged user (e.g. remote supervisor) to authorize running system commands on the operating system. These include shutting down the system, launching task manager or running arbitrary system commands. An authorized user must successfully provide the correct response code to a challenge code presented by the CRS RetailStore software. This can be bypassed by exploiting the vulnerability identified below.  
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STEPS TO IDENTIFY VULNERABILITY  
  
- From the POS main screen,  
1. Click F1 Help button  
2. Click F5 Void Last Item  
3. Right click on Help window  
4. Click View Source  
5. Insert some JavaScript into the HTML file which creates a button to spawn a command shell  
6. Save file  
7. Right click on Help window  
8. Click Refresh  
9. Click the newly created button that will spawn a shell  
10. If a prompt appears asking for permissions to run ActiveX, click “Yes”  
  
During the test, the system was observed to run the Windows command prompt on Windows XP Embedded. This was performed using an ActiveX JavaScript payload.  
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RECOMMENDED ACTIONS  
For systems which are using the affected software, the following actions are advised:  
* Upgrade affected systems to the latest stable version of CRS Retail Store  
* Consider upgrading Windows operating systems to later stable versions such as Windows Embedded 8.1 Industry  
* Ensure proper network segmentation and firewalls are configured and placed correctly for networks containing such systems  
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TIMELINE  
All times provided in GMT +8  
2014 July: Security issue found on CRS Retail Store software. Issue reported to vendor for fix through Epicor client. April 2015 given as date for completion of patch deployment.  
2015 Feb 17: Email sent to [email protected] to confirm that the vulnerability had been fixed. There was no reply.  
2015 Feb 28: Email sent to [email protected] for update on earlier email. There was no reply.  
2015 Mar 4: Request sent to CVE assignment team, MITRE CVE Numbering Authority for CVE identifier  
2015 Mar 5: CVE-2015-2210 is assigned by CVE assignment team, MITRE CVE Numbering Authority  
2015 Mar 18: Call made to Epicor Corporate HQ (+15123282300) at 10:01:39 PM. Recipient of call did not seem to understand about security issue.  
2015 Mar 21: Issue reported to CERT(R) Coordination Center. Issue tagged as VU#255588.  
CERT Vulnerability Analysis Team declines to publish issue due to local exploitation and advises that   
"if the vendor is unresponsive, publishing via SecurityFocus or another mailing list after some time (we recommend allowing 45 days for a vendor response) is an option."  
2015 May 2: Security advisory released for the purpose of preventing such attacks by notifying public of need to mitigate vulnerability.  
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SEVERITY RATING  
CVSS v2 Score: 5.3 (AV:L/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:OF/RC:C)  
CVSS v3 Preview 2 Score: 6.7 (CVSS:3.0/AV:P/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C)  
Official patch assumed for this calculation.  
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