---
id: CVE-2026-103679
title: A flaw was found in tnef
summary: >-
  A flaw was found in tnef. A remote attacker could exploit this vulnerability
  by providing a specially crafted Transport Neutral Encapsulation Format (TNEF)
  file containing multiple message bodies. During extraction, improper memory
  manag…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'
cwe:
  - CWE-416
product: tnef
affected:
  - tnef <= 1.4.18
published: '2026-10-01'
updated: '2026-10-01'
sourceUpdated: '2026-10-01T13:02:09.610'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-103679'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-103679'
    label: patrick@puiterwijk.org
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2544477'
    label: patrick@puiterwijk.org
  - url: 'https://github.com/verdammelt/tnef'
    label: patrick@puiterwijk.org
tags:
  - nvd
  - cve.org
ingestedAt: '2026-10-01T12:43:54.810Z'
---

## Overview

A flaw was found in tnef. A remote attacker could exploit this vulnerability by providing a specially crafted Transport Neutral Encapsulation Format (TNEF) file containing multiple message bodies. During extraction, improper memory management triggers a use-after-free and double-free condition, causing the application to crash and resulting in a Denial of Service (DoS).

## Remediation

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