CVE-2025-55648 Overview
CVE-2025-55648 is a heap buffer overflow vulnerability in GPAC MP4Box v2.4. The flaw resides in the gf_opus_parse_packet_header function within media_tools/av_parsers.c. An attacker can trigger the overflow by supplying a crafted MP4 file to the parser. Successful exploitation causes a Denial of Service (DoS) condition in the affected process. The vulnerability is tracked under CWE-122: Heap-based Buffer Overflow and requires local access with user interaction to open the malicious file.
Critical Impact
A crafted MP4 file processed by GPAC MP4Box v2.4 causes a heap buffer overflow in the Opus packet header parser, leading to application crash and denial of service.
Affected Products
- GPAC MP4Box v2.4
- GPAC media framework distributions bundling the vulnerable av_parsers.c
- Downstream tools and pipelines invoking gf_opus_parse_packet_header for MP4 parsing
Discovery Timeline
- 2026-06-15 - CVE-2025-55648 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-55648
Vulnerability Analysis
The vulnerability is a heap-based buffer overflow [CWE-122] inside the gf_opus_parse_packet_header function in media_tools/av_parsers.c. The function parses Opus audio packet headers embedded in MP4 containers. When MP4Box processes a crafted file, the parser writes or reads beyond the bounds of a heap-allocated buffer. The result is memory corruption that terminates the MP4Box process. Confidentiality and integrity are not impacted, but availability is fully compromised for the parsing workflow.
Root Cause
The root cause is missing or insufficient bounds validation when parsing Opus packet header fields. The parser trusts size and offset values supplied by the input file without verifying them against the allocated buffer length. When a manipulated header advertises a length that exceeds the heap allocation, the function accesses memory outside the intended region. This produces undefined behavior and crashes the process when the corrupted memory is dereferenced.
Attack Vector
The attack requires local access and user interaction. An attacker delivers a crafted MP4 file to a victim through email, file sharing, or a download. When the user processes the file with MP4Box v2.4, the parser triggers the overflow. The vulnerability cannot be exploited remotely without user action, and it does not require authentication. Automated media processing pipelines that ingest untrusted MP4 files face elevated risk because user interaction is effectively replaced by automated file handling.
No verified public proof-of-concept code is currently available. Refer to the Openwall OSS Security Update for additional technical detail.
Detection Methods for CVE-2025-55648
Indicators of Compromise
- Unexpected MP4Box process crashes or segmentation faults during MP4 ingestion
- Core dumps referencing gf_opus_parse_packet_header or av_parsers.c in the stack trace
- MP4 files with malformed Opus packet headers arriving from untrusted sources
Detection Strategies
- Run MP4Box under AddressSanitizer (ASan) in test environments to surface heap overflows in gf_opus_parse_packet_header
- Hash-match incoming MP4 files against known crafted samples shared via OSS-Security mailing list reports
- Inspect process exit codes and crash telemetry from media transcoding services for abnormal termination patterns
Monitoring Recommendations
- Forward MP4Box crash logs and core dumps to a centralized log platform for correlation
- Monitor file-processing services for repeated abnormal exits tied to the same input file hash
- Track GPAC version inventory across build pipelines, CI runners, and media servers to flag v2.4 deployments
How to Mitigate CVE-2025-55648
Immediate Actions Required
- Identify all systems running GPAC MP4Box v2.4 across endpoints, servers, and container images
- Restrict MP4Box processing to trusted MP4 sources until a patched version is deployed
- Sandbox MP4Box execution using containers, seccomp, or AppArmor to contain crashes
- Disable automated MP4 ingestion pipelines that accept files from untrusted users
Patch Information
No official vendor patch reference is published in the NVD entry at the time of writing. Track the GPAC project repository and the InfoSec Exchange advisory post for fix availability. Upgrade to a release that includes corrected bounds checking in gf_opus_parse_packet_header once available.
Workarounds
- Reject MP4 files containing Opus audio tracks at the gateway until a patched build is deployed
- Pre-validate MP4 file structure with an alternative parser before passing input to MP4Box
- Execute MP4Box under a non-privileged service account with strict filesystem and resource limits
# Example: run MP4Box in a restricted systemd unit
# /etc/systemd/system/mp4box-sandbox.service
[Service]
ExecStart=/usr/bin/MP4Box -info /var/input/%i.mp4
User=mp4box
NoNewPrivileges=true
PrivateTmp=true
ProtectSystem=strict
MemoryMax=512M
LimitCORE=0
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
