Denial of Service (DoS) Affecting libpq Open this link in a new tab package, versions *

  • Exploit Maturity

    Proof of concept

  • Attack Complexity


  • Availability


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  • snyk-id


  • published

    14 Jun 2022

  • disclosed

    3 Feb 2022

  • credit

    Cristian-Alexandru Staicu, Snyk Security Labs

How to fix?

There is no fixed version for libpq.


libpq is a node native bindings to the PostgreSQL libpq C client library.

Affected versions of this package are vulnerable to Denial of Service (DoS) when the addons attempt to cast the second argument to an array and fail. This happens for every non-array argument passed.

Note: pg-native is a mere binding to npm's libpq library, which in turn has the addons and bindings to the actual C libpq library. This means that problems found in pg-native may transitively impact npm's libpq.


//pg-native -> poc.js

let Client = require('pg-native') 
let client = new Client(); 
client.query('some str', 1, function() {});

//libpq -> poc.js

var Libpq = require('libpq') 
const pq = new Libpq(); 
pq.sendQueryParams("some str", 1) 


Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

  • High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

  • Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package