CVE-2026-57253: Foxit PDF Editor DOS Vulnerability

CVE-2026-57253 Overview

CVE-2026-57253 is an out-of-bounds read vulnerability [CWE-125] affecting Foxit PDF Editor and Foxit PDF Reader on Microsoft Windows. A malformed image object embedded in a PDF causes the renderer to enter an incorrect processing branch. During scan line conversion, the code dereferences an invalid image buffer pointer, which crashes the application.

The flaw requires local access and user interaction, such as opening a crafted PDF document. Successful exploitation results in application termination and potential exposure of adjacent memory contents.

Critical Impact
A crafted PDF containing a malformed image object crashes Foxit PDF Editor or Reader through an invalid buffer pointer dereference during scan line conversion, producing a denial of service condition.

Affected Products

Foxit PDF Editor on Microsoft Windows
Foxit PDF Reader on Microsoft Windows
Microsoft Windows platform installations of Foxit PDF applications

Discovery Timeline

2026-07-08 - CVE-2026-57253 published to NVD
2026-07-09 - Last updated in NVD database

Technical Details for CVE-2026-57253

Vulnerability Analysis

The vulnerability resides in the image rendering pipeline of Foxit PDF Editor and Reader. When the parser encounters an abnormal image object, the renderer selects an incorrect processing branch that was not designed to handle the malformed structure. This branch proceeds without validating the image buffer pointer.

During the scan line conversion phase, the renderer reads pixel data using this invalid pointer. The out-of-bounds read [CWE-125] accesses memory outside the intended buffer boundary, causing the application to crash. The condition falls under the out-of-bounds read weakness class, which can also disclose fragments of process memory before termination.

Root Cause

The root cause is missing validation of the image buffer pointer before scan line conversion. The renderer branches on image object attributes without confirming that the associated buffer was properly initialized. When an attacker supplies an abnormal image object, the branch selection logic dispatches to code that assumes a valid buffer, and the subsequent read operation touches unmapped or unintended memory.

Attack Vector

An attacker crafts a PDF file containing an abnormal image object and delivers it to the target through email, web download, or shared storage. The user must open the file in a vulnerable version of Foxit PDF Editor or Reader on Windows. When the renderer processes the image, the wrong branch executes and the application crashes.

The attack vector is local and requires user interaction. No authentication is required. The impact is limited to availability, with confidentiality impact tied to potential memory disclosure through the invalid read.

No public proof-of-concept code has been published for CVE-2026-57253. Technical details are available in the Foxit Security Bulletin.

Detection Methods for CVE-2026-57253

Indicators of Compromise

Unexpected crashes of FoxitPDFEditor.exe or FoxitPDFReader.exe shortly after opening a PDF document
Windows Error Reporting entries citing access violation exceptions in Foxit rendering modules
PDF files containing malformed image XObjects with inconsistent width, height, or color space parameters

Detection Strategies

Monitor application crash telemetry for Foxit PDF processes and correlate crashes with recently opened PDF files
Inspect PDF attachments at email and web gateways for malformed image object structures
Track process creation events where Foxit binaries terminate abnormally following a document open operation

Monitoring Recommendations

Enable Windows Error Reporting collection for Foxit binaries and forward events to centralized logging
Alert on repeated Foxit crashes originating from the same document source or user
Review endpoint logs for PDF file writes from untrusted sources followed by Foxit process launches

How to Mitigate CVE-2026-57253

Immediate Actions Required

Update Foxit PDF Editor and Foxit PDF Reader to the latest version listed in the vendor security bulletin
Restrict opening of PDF files received from untrusted sources until patching is complete
Inventory Windows endpoints running Foxit PDF applications to confirm patch coverage

Patch Information

Foxit has published remediation guidance in the Foxit Security Bulletin. Administrators should review the bulletin for fixed version numbers and apply updates through the built-in updater or enterprise deployment tools.

Workarounds

Configure Foxit PDF applications to disable automatic rendering of embedded images where feasible
Route incoming PDF documents through a sandboxed viewer or gateway that renders content in an isolated environment
Enforce application control policies that block execution of Foxit binaries when unpatched versions are detected

bash

# Query installed Foxit versions across Windows endpoints via PowerShell
Get-WmiObject -Class Win32_Product |
  Where-Object { $_.Name -like "*Foxit*" } |
  Select-Object Name, Version, InstallDate