---
id: CVE-2026-18495
title: A flaw was found in libtiff
summary: >-
  A flaw was found in libtiff. A heap-buffer overflow vulnerability exists in
  the `tiff2pdf` utility due to an integer truncation error when processing
  crafted BigTIFF files. An attacker can provide a specially crafted BigTIFF
  file, causin…
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:H'
cwe:
  - CWE-122
vendor: Red Hat
product: libtiff-main
affected:
  - libtiff-main (all versions)
  - ceph
  - ceph
  - ceph
  - ceph
  - ceph
  - boost
  - ceph
  - libtiff
  - libtiff
  - compat-libtiff3
  - libtiff
  - compat-libtiff3
  - libtiff
  - mingw-libtiff
  - boost
  - ceph
  - libtiff
  - boost
published: '2026-09-11'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:42:43.623'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-18495'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:53467'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-18495'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2531414'
    label: secalert@redhat.com
  - url: 'https://gitlab.com/libtiff/libtiff/-/merge_requests/729'
    label: secalert@redhat.com
  - url: >-
      https://gitlab.com/libtiff/libtiff/-/tree/67fd283d276f09db54dc39b9ef7b979d4b45c4b1
    label: secalert@redhat.com
tags:
  - nvd
  - cve.org
epss: 0.00117
epssPercentile: 0.01483
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-11T17:56:50.884605Z'
ingestedAt: '2026-09-14T00:35:28.535Z'
---

## Overview

A flaw was found in libtiff. A heap-buffer overflow vulnerability exists in the `tiff2pdf` utility due to an integer truncation error when processing crafted BigTIFF files. An attacker can provide a specially crafted BigTIFF file, causing a 64-bit `StripByteCounts` value to be truncated to a 32-bit integer. This leads to an undersized memory allocation and a subsequent out-of-bounds memory copy, resulting in a crash and severe memory corruption.

## Remediation

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