---
id: CVE-2026-17591
title: 'Libarchive: libarchive: use-after-free via aliased mac metadata copy'
summary: >-
  A flaw was found in libarchive. An attacker can cause a Denial of Service
  (DoS) or potential information disclosure due to a use-after-free
  vulnerability, which occurs when a program reads memory that has already been
  released. This issu…
severity: low
cvss: 3.6
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L'
cvssSource: cna
cwe:
  - CWE-416
vendor: Red Hat
product: libarchive
affected:
  - libarchive (all versions)
  - libarchive (all versions)
  - libarchive (all versions)
  - libarchive (all versions)
  - libarchive (all versions)
  - libarchive (all versions)
published: '2026-10-16'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T22:03:40.603Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-17591'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-17591'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2554209'
    label: RHBZ#2554209
  - url: 'https://github.com/libarchive/libarchive/pull/3318'
tags:
  - cve.org
ingestedAt: '2026-10-16T22:54:45.854Z'
---

## Overview

A flaw was found in libarchive. An attacker can cause a Denial of Service (DoS) or potential information disclosure due to a use-after-free vulnerability, which occurs when a program reads memory that has already been released. This issue arises when the archive_entry_copy_mac_metadata() function deallocates an internal buffer before completing a data copy. An attacker who can supply input to an application utilizing this function can trigger the flaw to crash the application or read uninitialized memory data.

## Affected

- `libarchive (all versions)`
- `libarchive (all versions)`
- `libarchive (all versions)`
- `libarchive (all versions)`
- `libarchive (all versions)`
- `libarchive (all versions)`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.