CVE-2026-57248: Foxit PDF Editor DOS Vulnerability

CVE-2026-57248 Overview

CVE-2026-57248 is a memory corruption vulnerability affecting Foxit PDF Editor and Foxit PDF Reader on Microsoft Windows. The flaw occurs when the application opens a PDF file and embedded JavaScript writes annotation attributes without sufficient object type and argument validation. Damage to the internal annotation structure results in application instability during subsequent release operations. The vulnerability is classified under [CWE-763] (Release of Invalid Pointer or Reference) and requires user interaction to trigger through a crafted PDF file.

Critical Impact
A local attacker who convinces a user to open a malicious PDF can corrupt annotation memory structures, causing the application to crash with potential for further exploitation impacting confidentiality, integrity, and availability.

Affected Products

Foxit PDF Editor (Windows)
Foxit PDF Reader (Windows)
Microsoft Windows (host operating system)

Discovery Timeline

2026-07-08 - CVE-2026-57248 published to NVD
2026-07-09 - Last updated in NVD database

Technical Details for CVE-2026-57248

Vulnerability Analysis

The vulnerability resides in how Foxit's PDF processing engine handles annotation attribute writes performed by JavaScript embedded in a PDF document. When JavaScript within a PDF file writes to annotation attributes, the application fails to perform adequate object type checks and argument validation. This gap allows the internal annotation structure to be corrupted during document processing.

The corrupted state does not immediately crash the application. Instead, damage manifests later when the application attempts to release the affected annotation objects. At release time, the invalid internal state triggers memory corruption behavior consistent with [CWE-763].

Root Cause

The root cause is missing type enforcement and argument validation in the JavaScript-to-annotation attribute write path. The engine trusts caller-supplied values without verifying object type compatibility, allowing malformed data to persist in annotation memory structures. The mismatch between expected and actual object types corrupts internal bookkeeping used during object teardown.

Attack Vector

Exploitation requires local access with user interaction. An attacker crafts a PDF file containing malicious JavaScript that writes annotation attributes designed to corrupt internal structures. The user must open the PDF in a vulnerable version of Foxit PDF Editor or Foxit PDF Reader. Once the document is opened and processed, the malformed writes propagate through annotation handling. The application then crashes during release of the corrupted annotation objects, and the resulting memory state may be leveraged for further impact on confidentiality, integrity, and availability.

No verified public proof-of-concept code is currently available. Refer to the Foxit Security Bulletins for vendor-published technical details.

Detection Methods for CVE-2026-57248

Indicators of Compromise

Unexpected crashes of FoxitPDFReader.exe or FoxitPDFEditor.exe immediately following the opening of a PDF file
Windows Error Reporting (WER) entries referencing Foxit binaries with access violation or heap corruption faults
PDF documents originating from untrusted sources that contain embedded JavaScript performing annotation attribute writes

Detection Strategies

Inspect inbound PDF files for embedded JavaScript that manipulates annotation objects, particularly writes to typed annotation properties
Correlate PDF open events with subsequent process crashes of Foxit executables within a short time window
Monitor endpoint telemetry for abnormal child process creation or memory anomalies originating from Foxit processes

Monitoring Recommendations

Enable process crash and exception logging on endpoints running Foxit PDF Editor or Foxit PDF Reader
Ingest email and web gateway logs to identify delivery of PDF attachments from untrusted senders
Alert on repeated Foxit application crashes across multiple hosts, which may indicate a coordinated exploitation attempt

How to Mitigate CVE-2026-57248

Immediate Actions Required

Apply the latest security updates for Foxit PDF Editor and Foxit PDF Reader as published in the Foxit Security Bulletins
Inventory all Windows endpoints running Foxit PDF products and prioritize patching on high-risk user workstations
Instruct users to avoid opening PDF files received from untrusted sources until patching is complete

Patch Information

Foxit publishes fixed versions and mitigation guidance through its security bulletin portal. Administrators should consult the Foxit Security Bulletins for the specific fixed build numbers and deployment instructions applicable to their environment.

Workarounds

Disable JavaScript execution in Foxit PDF Editor and Reader via Preferences > JavaScript > Enable JavaScript Actions until patches are applied
Configure email and web filtering rules to strip or quarantine PDF attachments containing embedded JavaScript
Restrict PDF file associations so untrusted documents open in a sandboxed viewer rather than the full Foxit application

bash

# Configuration example - disable JavaScript in Foxit via Windows registry
reg add "HKCU\Software\Foxit Software\Foxit PDF Reader\Preferences\JavaScript" /v bEnableJS /t REG_DWORD /d 0 /f
reg add "HKCU\Software\Foxit Software\Foxit PDF Editor\Preferences\JavaScript" /v bEnableJS /t REG_DWORD /d 0 /f