CVE-2025-70305: GPAC Stack Overflow DoS Vulnerability

CVE-2025-70305 Overview

A stack overflow vulnerability exists in the dmx_saf function of GPAC v2.4.0, an open-source multimedia framework used for creating, packaging, and streaming rich media content. This vulnerability allows attackers to cause a Denial of Service (DoS) condition by providing a specially crafted .saf file to the application.

Critical Impact
Attackers can crash GPAC applications by supplying malicious SAF files, potentially disrupting media processing workflows and services that rely on GPAC for multimedia handling.

Affected Products

GPAC v2.4.0
Applications and services utilizing GPAC's SAF file processing functionality

Discovery Timeline

2026-01-15 - CVE CVE-2025-70305 published to NVD
2026-01-16 - Last updated in NVD database

Technical Details for CVE-2025-70305

Vulnerability Analysis

This vulnerability is classified as CWE-121 (Stack-based Buffer Overflow). The flaw resides in the dmx_saf function, which is responsible for demultiplexing SAF (Scalable Application Framework) files within GPAC. When processing a maliciously crafted .saf file, the function fails to properly validate input boundaries, leading to a stack overflow condition.

The vulnerability requires local access to exploit, as an attacker must convince a user to open a malicious SAF file or place the file where it will be automatically processed by a GPAC-based application. While no remote code execution has been demonstrated, the stack overflow reliably causes application crashes, resulting in denial of service.

Root Cause

The root cause is improper boundary checking within the dmx_saf function when parsing SAF file structures. The function allocates stack-based buffers without adequately validating the size of incoming data from the SAF file. When oversized or malformed data is encountered, it overwrites adjacent stack memory, corrupting the stack frame and causing the application to crash.

Attack Vector

The attack vector is local, requiring user interaction to open or process a malicious .saf file. Attack scenarios include:

Direct file opening: An attacker sends a malicious SAF file to a victim who opens it with a GPAC-based media player or processing tool
Automated processing: Systems that automatically process SAF files from untrusted sources (such as media conversion services) could be targeted
File share attacks: Placing malicious SAF files in shared directories where GPAC applications may scan or preview files

Technical details regarding the specific malformed SAF file structure that triggers the overflow can be found in the GitHub PoC Repository.

Detection Methods for CVE-2025-70305

Indicators of Compromise

Unexpected crashes of GPAC-based applications when processing SAF files
Crash dumps indicating stack corruption in the dmx_saf function
Presence of unusually structured or oversized .saf files in media directories

Detection Strategies

Monitor for repeated GPAC process crashes with stack-related error codes
Implement file integrity monitoring for SAF files in media processing directories
Deploy endpoint detection rules to identify abnormal SAF file characteristics (unusual size ratios, malformed headers)
Review application logs for parsing errors related to SAF file handling

Monitoring Recommendations

Enable crash reporting and analysis for all GPAC-based applications
Monitor system stability metrics for services utilizing GPAC multimedia processing
Implement file scanning policies for incoming SAF files before processing
Track process termination events for GPAC binaries

How to Mitigate CVE-2025-70305

Immediate Actions Required

Restrict processing of SAF files from untrusted sources until a patch is applied
Implement input validation for SAF files before passing them to GPAC
Consider disabling SAF file support if not required for operations
Update GPAC to a patched version when available from the vendor

Patch Information

No official patch information is available at this time. Organizations should monitor the GPAC project's official channels for security updates. The vulnerability was documented in a proof-of-concept repository which may contain additional remediation guidance.

Workarounds

Implement file type filtering to block SAF files at network boundaries and email gateways
Use sandboxing or containerization for GPAC processes to limit the impact of crashes
Deploy application whitelisting to prevent unauthorized GPAC execution
Consider using alternative media processing libraries for SAF files until a fix is available

bash

# Example: Restrict SAF file processing permissions
chmod 000 /path/to/saf/processing/directory
# Or configure GPAC to skip SAF demuxing if possible
# Check GPAC documentation for runtime configuration options