CVE-2024-9751 Overview
CVE-2024-9751 is an out-of-bounds read vulnerability [CWE-125] in Tungsten Automation Power PDF. The flaw exists in the parser that handles JPEG 2000 (JP2) image files embedded in PDF documents. Insufficient validation of user-supplied data allows a read past the end of an allocated object. An attacker who convinces a user to open a crafted file or visit a malicious page can execute code in the context of the current process. The issue was reported through the Zero Day Initiative as ZDI-CAN-24468 and published as advisory ZDI-24-1363.
Critical Impact
Successful exploitation gives attackers arbitrary code execution with the privileges of the user running Power PDF, enabling malware installation, data theft, or lateral movement.
Affected Products
- Tungsten Automation Power PDF (all versions prior to the vendor fix)
- Products bundling the vulnerable JP2 parsing component
- Workstations processing untrusted PDF documents with Power PDF
Discovery Timeline
- 2024-11-22 - CVE-2024-9751 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-9751
Vulnerability Analysis
The vulnerability resides in the routine that parses JP2 (JPEG 2000) image streams inside PDF files. Power PDF fails to properly validate length or offset fields supplied by the input file. During parsing, the code reads bytes beyond the bounds of an allocated buffer. This adjacent memory can contain pointers, object metadata, or heap management structures. Attackers who influence heap layout can turn the disclosure primitive into arbitrary code execution. Exploitation requires user interaction, typically opening a malicious PDF or navigating to a page that triggers Power PDF to process one.
Root Cause
The root cause is the absence of proper bounds checking on user-controlled fields inside the JP2 codestream. When the parser dereferences an attacker-controlled length or index without verifying it against the allocated object size, it reads out of bounds. This aligns with the CWE-125 classification. Technical mechanics are documented in the Zero Day Initiative Advisory ZDI-24-1363.
Attack Vector
An attacker crafts a PDF that embeds a malformed JP2 image. The victim opens the file locally or via a browser handler associated with Power PDF. Parsing the malformed stream triggers the out-of-bounds read. Combined with heap grooming, an attacker can pivot the read into control-flow hijack and execute arbitrary code as the current user. No network privileges or credentials are required on the target host.
No verified public proof-of-concept code is available. Refer to the ZDI advisory for exploitation specifics.
Detection Methods for CVE-2024-9751
Indicators of Compromise
- Unexpected child processes spawned by Power PDF executables shortly after a document open event.
- PDF files containing malformed or unusually structured JP2 image streams delivered via email or web downloads.
- Crashes or Windows Error Reporting entries referencing Power PDF modules during PDF rendering.
Detection Strategies
- Inspect PDF attachments for embedded JP2 streams with anomalous marker segments or size fields using content-disarm or file-analysis tooling.
- Alert on Power PDF processes performing network egress, credential access, or writing executables to disk.
- Correlate document-open telemetry with process-tree anomalies to identify exploitation attempts.
Monitoring Recommendations
- Collect endpoint process, file, and image-load telemetry from workstations running Power PDF.
- Monitor email and web gateways for PDFs originating from untrusted senders and quarantine samples with malformed JPEG 2000 content.
- Track crash telemetry from Power PDF as a proxy for attempted or failed exploitation.
How to Mitigate CVE-2024-9751
Immediate Actions Required
- Inventory all endpoints with Tungsten Automation Power PDF installed and prioritize patch deployment.
- Restrict opening of PDFs from untrusted sources until fixed builds are in place.
- Disable browser handlers that automatically launch Power PDF for downloaded documents.
Patch Information
Apply the vendor-supplied update referenced in Zero Day Initiative Advisory ZDI-24-1363. Coordinate with Tungsten Automation for the specific fixed release covering your deployment channel.
Workarounds
- Block or strip PDFs containing JPEG 2000 image streams at the email and web gateway where feasible.
- Change the default handler for .pdf files to a hardened alternative reader until Power PDF is patched.
- Enforce application allowlisting to prevent unknown executables spawned by Power PDF from running.
# Windows: reassign default PDF handler via Group Policy or DISM XML
# Example DefaultAssociations.xml fragment to remove Power PDF as default
<Association Identifier=".pdf" ProgId="MSEdgePDF" ApplicationName="Microsoft Edge" />
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
