---
id: CVE-2025-58183
aliases:
  - GO-2025-4014
  - BIT-golang-2025-58183
title: Unbounded allocation when parsing GNU sparse map in archive/tar
summary: Unbounded allocation when parsing GNU sparse map in archive/tar
severity: none
vendor: stdlib
product: stdlib
ecosystem: go
affected:
  - 'stdlib >= 1.25.0, < 1.25.2'
patched:
  - stdlib 1.25.2
published: '2025-10-29'
updated: '2026-07-23'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GO-2025-4014'
references:
  - url: 'https://go.dev/cl/709861'
  - url: 'https://go.dev/issue/75677'
  - url: 'https://groups.google.com/g/golang-announce/c/4Emdl2iQ_bI'
tags:
  - osv
  - go
epss: 0.00413
epssPercentile: 0.32894
ingestedAt: '2026-07-23T19:05:54.007Z'
---

## Overview

tar.Reader does not set a maximum size on the number of sparse region data blocks in GNU tar pax 1.0 sparse files. A maliciously-crafted archive containing a large number of sparse regions can cause a Reader to read an unbounded amount of data from the archive into memory. When reading from a compressed source, a small compressed input can result in large allocations.

## Affected packages

- `stdlib >= 1.25.0, < 1.25.2`

## Remediation

Upgrade to a patched release:

- `stdlib 1.25.2`