Package Instance

org.postgresql:postgresql vulnerable to SQL Injection via line comment generation
# Impact
SQL injection is possible when using the non-default connection property `preferQueryMode=simple` in combination with application code that has a vulnerable SQL that negates a parameter value.

There is no vulnerability in the driver when using the default query mode. Users that do not override the query mode are not impacted.

# Exploitation

To exploit this behavior the following conditions must be met:

1. A placeholder for a numeric value must be immediately preceded by a minus (i.e. `-`)
1. There must be a second placeholder for a string value after the first placeholder on the same line. 
1. Both parameters must be user controlled.

The prior behavior of the driver when operating in simple query mode would inline the negative value of the first parameter and cause the resulting line to be treated as a `--` SQL comment. That would extend to the beginning of the next parameter and cause the quoting of that parameter to be consumed by the comment line. If that string parameter includes a newline, the resulting text would appear unescaped in the resulting SQL.

When operating in the default extended query mode this would not be an issue as the parameter values are sent separately to the server. Only in simple query mode the parameter values are inlined into the executed SQL causing this issue.

# Example

```java
PreparedStatement stmt = conn.prepareStatement("SELECT -?, ?");
stmt.setInt(1, -1);
stmt.setString(2, "\nWHERE false --");
ResultSet rs = stmt.executeQuery();
```

The resulting SQL when operating in simple query mode would be:

```sql
SELECT --1,'
WHERE false --'
```

The contents of the second parameter get injected into the command. Note how both the number of result columns and the WHERE clause of the command have changed. A more elaborate example could execute arbitrary other SQL commands.

# Patch
Problem will be patched upgrade to 42.7.2, 42.6.1, 42.5.5, 42.4.4, 42.3.9, 42.2.28, 42.2.28.jre7

The patch fixes the inlining of parameters by forcing them all to be serialized as wrapped literals. The SQL in the prior example would be transformed into:

```sql
SELECT -('-1'::int4), ('
WHERE false --')
```

# Workarounds
Do not use the connection property`preferQueryMode=simple`. (*NOTE: If you do not explicitly specify a query mode then you are using the default of `extended` and are not impacted by this issue.*)

Remote code execution vulnerability using plugin features
pgjdbc is the offical PostgreSQL JDBC Driver. A security hole was found in the jdbc driver for postgresql database while doing security research. The system using the postgresql library will be attacked when attacker control the jdbc url or properties. pgjdbc instantiates plugin instances based on class names provided via `authenticationPluginClassName`, `sslhostnameverifier`, `socketFactory`, `sslfactory`, `sslpasswordcallback` connection properties. However, the driver does not verify if the class implements the expected interface before instantiating the class. This can lead to remote code execution loaded via arbitrary classes.

Unescaped parameters in the PostgreSQL JDBC driver
Interaction error in the PostgreSQL JDBC driver before 8.2, when used with a PostgreSQL server with the "standard_conforming_strings" option enabled, such as the default configuration of PostgreSQL 9.1, does not properly escape unspecified JDBC statement parameters, which allows remote attackers to perform SQL injection attacks.  NOTE: as of 20120330, it was claimed that the upstream developer planned to dispute this issue, but an official dispute has not been posted as of 20121005.

PostgreSQL JDBC Driver SQL Injection in ResultSet.refreshRow() with malicious column names
### Impact
_What kind of vulnerability is it? Who is impacted?_

The PGJDBC implementation of the `java.sql.ResultRow.refreshRow()` method is not performing escaping of column names so a malicious column name that contains a statement terminator, e.g. `;`, could lead to SQL injection. This could lead to executing additional SQL commands as the application's JDBC user.

User applications that do not invoke the `ResultSet.refreshRow()` method are not impacted.

User application that do invoke that method are impacted if the underlying database that they are querying via their JDBC application may be under the control of an attacker. The attack requires the attacker to trick the user into executing SQL against a table name who's column names would contain the malicious SQL and subsequently invoke the `refreshRow()` method on the ResultSet.

For example:

```sql
CREATE TABLE refresh_row_example (
  id     int PRIMARY KEY,
  "1 FROM refresh_row_example; SELECT pg_sleep(10); SELECT * " int
);
```

This example has a table with two columns. The name of the second column is crafted to contain a statement terminator followed by additional SQL. Invoking the `ResultSet.refreshRow()` on a ResultSet that queried this table, e.g. `SELECT * FROM refresh_row`, would cause the additional SQL commands such as the `SELECT pg_sleep(10)` invocation to be executed.

As the multi statement command would contain multiple results, it would not be possible for the attacker to get data directly out of this approach as the `ResultSet.refreshRow()` method would throw an exception. However, the attacker could execute any arbitrary SQL including inserting the data into another table that could then be read or any other DML / DDL statement.

Note that the application's JDBC user and the schema owner need not be the same. A JDBC application that executes as a privileged user querying database schemas owned by potentially malicious less-privileged users would be vulnerable. In that situation it may be possible for the malicious user to craft a schema that causes the application to execute commands as the privileged user.

### Patches
_Has the problem been patched? What versions should users upgrade to?_

Yes, versions 42.2.26, 42.3.7, and 42.4.1 have been released with a fix.

### Workarounds
_Is there a way for users to fix or remediate the vulnerability without upgrading?_

Check that you are not using the `ResultSet.refreshRow()` method.

If you are, ensure that the code that executes that method does not connect to a database that is controlled by an unauthenticated or malicious user. If your application only connects to its own database with a fixed schema with no DDL permissions, then you will not be affected by this vulnerability as it requires a maliciously crafted schema.

Path traversal in org.postgresql:postgresql
** DISPUTED ** In pgjdbc before 42.3.3, an attacker (who controls the jdbc URL or properties) can call java.util.logging.FileHandler to write to arbitrary files through the loggerFile and loggerLevel connection properties. An example situation is that an attacker could create an executable JSP file under a Tomcat web root. NOTE: the vendor's position is that there is no pgjdbc vulnerability; instead, it is a vulnerability for any application to use the pgjdbc driver with untrusted connection properties.

TemporaryFolder on unix-like systems does not limit access to created files
**Vulnerability**

`PreparedStatement.setText(int, InputStream)`
and

`PreparedStatemet.setBytea(int, InputStream)`

will create a temporary file if the InputStream is larger than 51k

 
Example of vulnerable code:

```java
String s = "some very large string greater than 51200 bytes";

PreparedStatement.setInputStream(1, new ByteArrayInputStream(s.getBytes()) );
```
This will create a temporary file which is readable by other users on Unix like systems, but not MacOS.

Impact
On Unix like systems, the system's temporary directory is shared between all users on that system. Because of this, when files and directories are written into this directory they are, by default, readable by other users on that same system.

This vulnerability does not allow other users to overwrite the contents of these directories or files. This is purely an information disclosure vulnerability.

When analyzing the impact of this vulnerability, here are the important questions to ask:

Is the driver running in an environment where the OS has other untrusted users.
If yes, and you answered 'yes' to question 1, this vulnerability impacts you.
If no, this vulnerability does not impact you.
Patches
Because certain JDK file system APIs were only added in JDK 1.7, this this fix is dependent upon the version of the JDK you are using.

Java 1.8 and higher users: this vulnerability is fixed in 42.2.27, 42.3.8, 42.4.3, 42.5.1
Java 1.7 users: this vulnerability is fixed in 42.2.27.jre7
Java 1.6 and lower users: no patch is available; you must use the workaround below.
Workarounds
If you are unable to patch, or are stuck running on Java 1.6, specifying the java.io.tmpdir system environment variable to a directory that is exclusively owned by the executing user will fix this vulnerability.

References
[CWE-200: Exposure of Sensitive Information to an Unauthorized Actor](https://cwe.mitre.org/data/definitions/200.html)
Fix commit https://github.com/pgjdbc/pgjdbc/commit/9008dc9aade6dbfe4efafcd6872ebc55f4699cf5
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