---
id: GO-2026-5841
aliases:
  - GHSA-259r-337f-4rfw
title: OOB read in github.com/klauspost/compress/s2
summary: OOB read in github.com/klauspost/compress/s2
severity: none
vendor: klauspost
product: github.com/klauspost/compress
ecosystem: go
affected:
  - 'github.com/klauspost/compress >= 1.16.0, < 1.18.7'
patched:
  - github.com/klauspost/compress 1.18.7
published: '2026-07-27'
updated: '2026-07-27'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GO-2026-5841'
references:
  - url: >-
      https://github.com/klauspost/compress/security/advisories/GHSA-259r-337f-4rfw
  - url: >-
      https://github.com/klauspost/compress/commit/8668e357e776d5152ed62f33c17f21b8690664fa
tags:
  - osv
  - go
ingestedAt: '2026-07-27T19:08:55.968Z'
---

## Overview

Providing a specially crafted dictionary to s2.NewDict and using it to encode data can make the encoder read out of bounds.

## Affected packages

- `github.com/klauspost/compress >= 1.16.0, < 1.18.7`

## Remediation

Upgrade to a patched release:

- `github.com/klauspost/compress 1.18.7`