This advisory follows up on two previous ICS-CERT Alerts:
- “ICS-ALERT-11-245-01—Multiple ActiveX Vulnerabilities in Advantech BroadWin WebAccess,” published September 2, 2011
- “ICS-ALERT-11-306-01—Advantech BroadWin WebAccess ActiveX Vulnerability,” published November 2, 2011
ICS-CERT received both coordinated and uncoordinated reports of eighteen vulnerabilities in BroadWin WebAccess. These vulnerabilities include:
• Cross-site scripting (XSS)
• SQL injection
• Cross-site report forgery (CSRF)
• Authentication issues
These vulnerabilities were reported separately by the nSense Vulnerability Coordination Team, Greg MacManus of iSIGHT Partners, Kuang-Chun Hung of Security Research and Service Institute−Information and Communication Security Technology Center (ICST), Luigi Auriemma, and Snake (alias).
ICS-CERT has coordinated with Advantech, which has released a new version of WebAccess that addresses most of the reported vulnerabilities.
These vulnerabilities affect all versions of Advantech/BroadWin WebAccess prior to applying the patch (V7.0) listed in the mitigations below.
An attacker can bypass authentication, gain administrative privileges, and remotely execute arbitrary code by exploiting these vulnerabilities. Impact to individual organizations depends on many factors that are unique to each organization.
ICS-CERT recommends that organizations evaluate the impact of this vulnerability based on their environment, architecture, and product implementation.
Advantech/BroadWin WebAccess is a web-based human-machine interface product used in energy, manufacturing, and building automation systems. The installation base is across Asia, North America, North Africa, and the Middle East.
WebAccess Client is available for computers running Windows 2000, XP, Vista, and Server 2003. A thin-client interface is available for Windows CE and Windows Mobile 5.0.
2. SQL INJECTION: An attacker can use a malformed URL address to execute an SQL injection attack. CVE-2012-0234 has been assigned to this vulnerability.
3. CROSS-SITE REQUEST FORGERY: An unauthenticated user can access restricted information using specific URL addresses. CVE-2012-0236 has been assigned to this vulnerability.
5. UNAUTHORIZED MODIFICATION: This vulnerability can be exploited by using specifically crafted URL addresses, which allows an unauthenticated user to enable or disable date and time syncing. CVE-2012-0237 has been assigned to this vulnerability.
6. STACK-BASED BUFFER OVERFLOW: A stack-based buffer overflow vulnerability exists in opcImg.asp that, when exploited, allows an attacker to remotely execute arbitrary code. CVE-2012-0238 has been assigned to this vulnerability.
7. AUTHENTICATION VULNERABILITY: An authentication vulnerability exists in uaddUpAdmin.asp in Advantech’s WebAccess 7.0—and possibly earlier versions—that, when exploited, allows an attacker to remotely change an administrator’s password. Exploit code is not required to exploit this vulnerability. CVE-2012-0239 has been assigned to this vulnerability.
8. AUTHENTICATION VULNERABILITY: An authentication vulnerability exists in GbScriptAddUp.asp that, when exploited, allows an attacker to remotely execute arbitrary code. CVE-2012-0240 has been assigned to this vulnerability.
9. ACTIVEX BUFFER OVERFLOW: A long string input to ActiveX parameters will cause a buffer overflow, which might allow remote attackers to execute arbitrary code and gain full control of the server. CVE-2011-4526 has been assigned to this vulnerability.
10.BUFFER OVERFLOW: This vulnerability exists because long string input to parameters will cause a buffer overflow, which could allow execution of arbitrary code. CVE-2011-4524 has been assigned to this vulnerability.
11.FILE MANIPULATION: An attacker can load any remote web page and write to a local batch file that will allow arbitrary code execution. CVE-2011-4525 has been assigned to this vulnerability.
12.SQL INJECTION: This vulnerability exists because string inputs are not checked, allowing attackers to perform SQL injection attacks.
13.CROSS-SITE SCRIPTING: This vulnerability exists because malicious cross-site scripts are allowed by parameters of bwerrdn.asp. CVE-2011-4522 has been assigned to this vulnerability.
14.CROSS-SITE SCRIPTING: This vulnerability exists because malicious cross-site scripts are allowed by parameters of bwview.asp. CVE-2011-4523 has been assigned to this vulnerability.
15.ARBITRARY MEMORY CORRUPTION: This vulnerability exists because functions are allowed to corrupt arbitrary memory zones through fully controllable stream identifiers. CVE-2012-0241 has been assigned to this vulnerability.
16.FORMAT STRING: A format string vulnerability can be exploited by the using a message string without the required format arguments. CVE-2012-0242 has been assigned to this vulnerability.
17.ACTIVEX BUFFER OVERFLOW: A component used by WebAccess, bwocxrun.ocx, is vulnerable to a buffer overflow vulnerability due to methods that are capable of creating a arbitrary file in arbitrary location. Exploitation could allow the execution of arbitrary code. CVE-2012-0243 has been assigned to this vulnerability.
18.SQL INJECTION: This vulnerability exists because string inputs are not checked on input, allowing attackers to perform many different SQL injection attacks. CVE-2012-0244 has been assigned to this vulnerability.
EXPLOITABILITY: All the vulnerabilities contained in this report are remotely exploitable.
EXISTENCE OF EXPLOIT: Public exploits are known to target these vulnerabilities.
DIFFICULTY: An attacker with low to moderate skill can exploit these vulnerabilities.
Advantech has created a new version of WebAccess (7.0) that addresses these vulnerabilities. This new version can be obtained at: http://webaccess.advantech.com/downloads.php. Advantech recommends that the new version be installed over the existing installation. If the existing version of WebAccess is uninstalled, the computer must be rebooted before reinstalling WebAccess.
Advantech recommends that customers using the WebAccess product refer to security considerations recommended by their installation manual.
For further assistance, customers should contact BroadWin support at
ICST, iSIGHT, and ICS-CERT have validated that the new version mitigates Vulnerabilities 1 and 5−16. For Vulnerabilities 2 and 3, the patched version fixes the issue for unauthenticated users; however, the problem still remains for nonadmin project users.
Vulnerability 4 was not patched, because Advantech does not consider it to be a security risk. Neither ICS-CERT nor independent researchers have validated that the new version resolves Vulnerabilities 17 and 18.
The full ICS-CERT adcisory can be found here: