CVE-2025-49850: PRJ File Parser Buffer Overflow Flaw

CVE-2025-49850 Overview

CVE-2025-49850 is a heap-based buffer overflow vulnerability [CWE-122] triggered during the parsing of PRJ files. The flaw stems from missing validation of user-supplied data when processing file content. An attacker who convinces a user to open a malicious PRJ file can corrupt heap memory by reading and writing past the end of allocated data structures. Successful exploitation can lead to arbitrary code execution in the context of the affected application.

The issue is tracked in CISA ICS Advisory ICSA-25-168-02, indicating relevance to industrial control system (ICS) environments where PRJ project files are commonly exchanged.

Critical Impact
Successful exploitation allows arbitrary code execution and full compromise of confidentiality, integrity, and availability on the affected host.

Affected Products

Industrial control system software referenced in CISA advisory ICSA-25-168-02
Applications that parse PRJ project files
Refer to the vendor advisory for specific affected versions

Discovery Timeline

2025-06-17 - CVE-2025-49850 published to the National Vulnerability Database (NVD)
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-49850

Vulnerability Analysis

The vulnerability resides in the routine responsible for parsing PRJ files. PRJ files contain project metadata used by engineering and ICS applications. The parser fails to enforce bounds checks on attacker-controlled fields before copying data into heap-allocated buffers.

When a crafted PRJ file is loaded, malformed length or offset values cause the application to read and write beyond the allocated buffer. This corrupts adjacent heap metadata and application objects. An attacker can leverage this corruption to hijack control flow and execute arbitrary code in the context of the user opening the file.

The vulnerability requires local file access and user interaction. The attack surface is consistent with engineering workstations where operators routinely open project files received from peers, contractors, or untrusted sources.

Root Cause

The root cause is improper validation of user-supplied data within the PRJ parser, classified under [CWE-122] Heap-based Buffer Overflow. The parser trusts size and offset fields embedded in the file without verifying them against allocated buffer boundaries. This allows attacker-controlled data to overflow heap structures.

Attack Vector

Exploitation requires an attacker to deliver a malicious PRJ file to a target and convince the user to open it in the vulnerable application. Common delivery mechanisms include phishing emails, shared network drives, removable media, and supply chain compromise of project file repositories. No network access to the target is required, and no prior authentication is needed.

No public proof-of-concept code is available for this vulnerability. Refer to the vendor advisory for additional technical details.

Detection Methods for CVE-2025-49850

Indicators of Compromise

Unexpected crashes or memory access violations in the application after opening PRJ files
PRJ files originating from untrusted email senders, external contractors, or unverified file shares
Anomalous child processes spawned by the engineering application after a PRJ file is opened
Unusual outbound network connections from the engineering workstation following file open events

Detection Strategies

Deploy behavioral endpoint identification to flag exploitation patterns such as shellcode execution from the affected application
Hunt for process lineage anomalies where the engineering application spawns command shells, scripting interpreters, or living-off-the-land binaries
Monitor Windows Error Reporting and application crash telemetry for repeated faults tied to PRJ file handling

Monitoring Recommendations

Log all PRJ file open events on engineering workstations and correlate against allowed file sources
Capture full process telemetry and command-line arguments to support post-incident reconstruction
Alert on engineering workstation processes making unexpected outbound connections or modifying registry persistence keys

How to Mitigate CVE-2025-49850

Immediate Actions Required

Apply vendor patches as referenced in CISA ICS Advisory ICSA-25-168-02 as soon as they are available
Restrict opening of PRJ files to those originating from trusted, verified sources
Isolate engineering workstations from general corporate network segments and the internet where feasible
Enforce least-privilege accounts on systems that handle project files to limit the impact of code execution

Patch Information

Consult the CISA ICS Advisory ICSA-25-168-02 and the corresponding vendor security bulletin for patched versions and update instructions. Track the advisory for any addenda that identify additional affected products or revised remediation steps.

Workarounds

Block PRJ file attachments at the email gateway when the file is not required for business operations
Use application allowlisting to prevent unauthorized child processes spawned by the engineering application
Validate the integrity and provenance of PRJ files through file hashing or digital signature checks before opening
Disable or sandbox the vulnerable application when patching is not immediately possible

bash

# Example: block PRJ attachments at a mail filter (pseudo-rule)
if attachment.extension == "prj" and sender.domain not in trusted_partners:
    action: quarantine
    notify: soc@example.com