---
id: CVE-2026-56869
aliases:
  - GO-2026-6168
title: >-
  Unbounded iteration count causes CPU denial of service in
  github.com/lib/pq/scram
summary: >-
  Unbounded iteration count causes CPU denial of service in
  github.com/lib/pq/scram
severity: none
vendor: lib
product: github.com/lib/pq
ecosystem: go
affected:
  - github.com/lib/pq >= 1.1.0
published: '2026-08-18'
updated: '2026-08-18'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GO-2026-6168'
references:
  - url: 'https://github.com/golang/vulndb/issues/6168'
tags:
  - osv
  - go
ingestedAt: '2026-08-18T19:21:39.025Z'
---

## Overview

The SCRAM client in github.com/lib/pq/scram accepts an attacker-controlled iteration count with no upper bound and immediately performs that many PBKDF2-style HMAC rounds. A PostgreSQL endpoint or active network attacker can send a valid SCRAM server-first message with a large iteration count (such as i=2147483647), causing client authentication to consume excessive CPU resources before verifying the server signature.

## Affected packages

- `github.com/lib/pq >= 1.1.0`

## Remediation

Refer to the advisory for the patched release.