Npgsql Vulnerable to SQL Injection via Protocol Message Size Overflow

Summary

Npgsql is the .NET data provider for PostgreSQL. The `WriteBind()` method in `src/Npgsql/Internal/NpgsqlConnector.FrontendMessages.cs` uses `int` variables to store the message length and the sum of parameter lengths. Both variables overflow when the sum of parameter lengths becomes too large. This causes Npgsql to write a message size that is too small when constructing a Postgres protocol message to send it over the network to the database. When parsing the message, the database will only read a small number of bytes and treat any following bytes as new messages while they belong to the old message. Attackers can abuse this to inject arbitrary Postgres protocol messages into the connection, leading to the execution of arbitrary SQL statements on the application's behalf. This vulnerability is fixed in 4.0.14, 4.1.13, 5.0.18, 6.0.11, 7.0.7, and 8.0.3.

Timeline

1. May 9, 2024, 2:29 PM UTCCVE published
2. May 9, 2024, 5:34 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: total

3. Dec 12, 2024, 8:56 PM UTCRecord last updated

Affected versions

• npgsql npgsql

  From 4.0.0 · fixed in 4.0.14; From 4.1.0 · fixed in 4.1.13; From 5.0.0 · fixed in 5.0.18; From 6.0.0 · fixed in 6.0.11; From 7.0.0 · fixed in 7.0.7; From 8.0.0 · fixed in 8.0.3

• NpgsqlNuGet

  From 8.0.0 · fixed in 8.0.3

• NpgsqlNuGet

  fixed in 4.0.14

• NpgsqlNuGet

  From 4.1.0 · fixed in 4.1.13

• NpgsqlNuGet

  From 5.0.0 · fixed in 5.0.18

• NpgsqlNuGet

  From 6.0.0 · fixed in 6.0.11

• NpgsqlNuGet

  From 7.0.0 · fixed in 7.0.7

References 15