CVE-2022-31197: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') (CWE-89)
value: PostgreSQL JDBC Driver (PgJDBC for short) allows Java programs to connect to a PostgreSQL database using standard, database independent Java code. 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. 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. Patched versions will be released as `42.2.26` and `42.4.1`. Users are advised to upgrade. There are no known workarounds for this issue.
CWE description: The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.
CVSS v3 base score: 8
Published: 2022-08-03T19:15Z
Repository: https://github.com/pgjdbc/pgjdbc
Language: Java
Files changed: pgjdbc/src/main/java/org/postgresql/jdbc/PgResultSet.java, pgjdbc/src/test/java/org/postgresql/test/jdbc2/Jdbc2TestSuite.java, pgjdbc/src/test/java/org/postgresql/test/jdbc2/ResultSetRefreshTest.java
Commit date: 2022-08-01 12:46:26 -0400
Commit message: Merge pull request from GHSA-r38f-c4h4-hqq2

Fixes SQL generated in PgResultSet.refresh() to escape column identifiers so as to prevent SQL injection.

Previously, the column names for both key and data columns in the table were copied as-is into the generated
SQL. This allowed a malicious table with column names that include statement terminator to be parsed and
executed as multiple separate commands.

Also adds a new test class ResultSetRefreshTest to verify this change.
Diff: diff --git a/pgjdbc/src/main/java/org/postgresql/jdbc/PgResultSet.java b/pgjdbc/src/main/java/org/postgresql/jdbc/PgResultSet.java
index 9ffaa1293..7519bdfc8 100644
--- a/pgjdbc/src/main/java/org/postgresql/jdbc/PgResultSet.java
+++ b/pgjdbc/src/main/java/org/postgresql/jdbc/PgResultSet.java
@@ -1416,21 +1416,22 @@ public class PgResultSet implements ResultSet, org.postgresql.PGRefCursorResultS
     PGResultSetMetaData pgmd = (PGResultSetMetaData) rsmd;
     for (int i = 1; i <= rsmd.getColumnCount(); i++) {
       if (i > 1) {
         selectSQL.append(", ");
       }
-      selectSQL.append(pgmd.getBaseColumnName(i));
+      Utils.escapeIdentifier(selectSQL, pgmd.getBaseColumnName(i));
     }
     selectSQL.append(" from ").append(onlyTable).append(tableName).append(" where ");
 
     List<PrimaryKey> primaryKeys = castNonNull(this.primaryKeys, "primaryKeys");
     int numKeys = primaryKeys.size();
 
     for (int i = 0; i < numKeys; i++) {
 
       PrimaryKey primaryKey = primaryKeys.get(i);
-      selectSQL.append(primaryKey.name).append(" = ?");
+      Utils.escapeIdentifier(selectSQL, primaryKey.name);
+      selectSQL.append(" = ?");
 
       if (i < numKeys - 1) {
         selectSQL.append(" and ");
       }
     }
diff --git a/pgjdbc/src/test/java/org/postgresql/test/jdbc2/Jdbc2TestSuite.java b/pgjdbc/src/test/java/org/postgresql/test/jdbc2/Jdbc2TestSuite.java
index fbb3136c5..3556e997c 100644
--- a/pgjdbc/src/test/java/org/postgresql/test/jdbc2/Jdbc2TestSuite.java
+++ b/pgjdbc/src/test/java/org/postgresql/test/jdbc2/Jdbc2TestSuite.java
@@ -116,10 +116,11 @@ import org.junit.runners.Suite;
     ReaderInputStreamTest.class,
     RefCursorTest.class,
     ReplaceProcessingTest.class,
     ResultSetMetaDataTest.class,
     ResultSetTest.class,
+    ResultSetRefreshTest.class,
     ReturningParserTest.class,
     SearchPathLookupTest.class,
     ServerCursorTest.class,
     ServerErrorTest.class,
     ServerPreparedStmtTest.class,
diff --git a/pgjdbc/src/test/java/org/postgresql/test/jdbc2/ResultSetRefreshTest.java b/pgjdbc/src/test/java/org/postgresql/test/jdbc2/ResultSetRefreshTest.java
new file mode 100644
index 000000000..023f2710b
--- /dev/null
+++ b/pgjdbc/src/test/java/org/postgresql/test/jdbc2/ResultSetRefreshTest.java
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2022, PostgreSQL Global Development Group
+ * See the LICENSE file in the project root for more information.
+ */
+
+package org.postgresql.test.jdbc2;
+
+import static org.junit.Assert.assertTrue;
+
+import org.postgresql.test.TestUtil;
+
+import org.junit.Test;
+
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+public class ResultSetRefreshTest extends BaseTest4 {
+  @Test
+  public void testWithDataColumnThatRequiresEscaping() throws Exception {
+    TestUtil.dropTable(con, "refresh_row_bad_ident");
+    TestUtil.execute(con, "CREATE TABLE refresh_row_bad_ident (id int PRIMARY KEY, \"1 FROM refresh_row_bad_ident; SELECT 2; SELECT *\" int)");
+    TestUtil.execute(con, "INSERT INTO refresh_row_bad_ident (id) VALUES (1), (2), (3)");
+
+    Statement stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE);
+    ResultSet rs = stmt.executeQuery("SELECT * FROM refresh_row_bad_ident");
+    assertTrue(rs.next());
+    try {
+      rs.refreshRow();
+    } catch (SQLException ex) {
+      throw new RuntimeException("ResultSet.refreshRow() did not handle escaping data column identifiers", ex);
+    }
+    rs.close();
+    stmt.close();
+  }
+
+  @Test
+  public void testWithKeyColumnThatRequiresEscaping() throws Exception {
+    TestUtil.dropTable(con, "refresh_row_bad_ident");
+    TestUtil.execute(con, "CREATE TABLE refresh_row_bad_ident (\"my key\" int PRIMARY KEY)");
+    TestUtil.execute(con, "INSERT INTO refresh_row_bad_ident VALUES (1), (2), (3)");
+
+    Statement stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE);
+    ResultSet rs = stmt.executeQuery("SELECT * FROM refresh_row_bad_ident");
+    assertTrue(rs.next());
+    try {
+      rs.refreshRow();
+    } catch (SQLException ex) {
+      throw new RuntimeException("ResultSet.refreshRow() did not handle escaping key column identifiers", ex);
+    }
+    rs.close();
+    stmt.close();
+  }
+}

Vulnerable code:       selectSQL.append(pgmd.getBaseColumnName(i));
      selectSQL.append(primaryKey.name).append(" = ?");
Fixed code:       Utils.escapeIdentifier(selectSQL, pgmd.getBaseColumnName(i));
      Utils.escapeIdentifier(selectSQL, primaryKey.name);
      selectSQL.append(" = ?");
    ResultSetRefreshTest.class,
/*
 * Copyright (c) 2022, PostgreSQL Global Development Group
 * See the LICENSE file in the project root for more information.
 */

package org.postgresql.test.jdbc2;

import static org.junit.Assert.assertTrue;

import org.postgresql.test.TestUtil;

import org.junit.Test;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class ResultSetRefreshTest extends BaseTest4 {
  @Test
  public void testWithDataColumnThatRequiresEscaping() throws Exception {
    TestUtil.dropTable(con, "refresh_row_bad_ident");
    TestUtil.execute(con, "CREATE TABLE refresh_row_bad_ident (id int PRIMARY KEY, \"1 FROM refresh_row_bad_ident; SELECT 2; SELECT *\" int)");
    TestUtil.execute(con, "INSERT INTO refresh_row_bad_ident (id) VALUES (1), (2), (3)");

    Statement stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE);
    ResultSet rs = stmt.executeQuery("SELECT * FROM refresh_row_bad_ident");
    assertTrue(rs.next());
    try {
      rs.refreshRow();
    } catch (SQLException ex) {
      throw new RuntimeException("ResultSet.refreshRow() did not handle escaping data column identifiers", ex);
    }
    rs.close();
    stmt.close();
  }

  @Test
  public void testWithKeyColumnThatRequiresEscaping() throws Exception {
    TestUtil.dropTable(con, "refresh_row_bad_ident");
    TestUtil.execute(con, "CREATE TABLE refresh_row_bad_ident (\"my key\" int PRIMARY KEY)");
    TestUtil.execute(con, "INSERT INTO refresh_row_bad_ident VALUES (1), (2), (3)");

    Statement stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE);
    ResultSet rs = stmt.executeQuery("SELECT * FROM refresh_row_bad_ident");
    assertTrue(rs.next());
    try {
      rs.refreshRow();
    } catch (SQLException ex) {
      throw new RuntimeException("ResultSet.refreshRow() did not handle escaping key column identifiers", ex);
    }
    rs.close();
    stmt.close();
  }
}