Vulnerability · Published May 26, 2026 · Assigned by VulDB

CVE-2026-9567GPAC MP4Box isom_intern.c MergeFragment null pointer dereference

Low 3.3

In plain English

A low-severity null pointer dereference in GPAC. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 2% of all known vulnerabilities).

Severity (CVSS 3.1)3.3Low

Exploit odds (30 days)0.1%top 98.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

A security flaw has been discovered in GPAC up to 2.4.0. Affected is the function MergeFragment of the file src/isomedia/isom_intern.c of the component MP4Box. The manipulation results in null pointer dereference. The attack needs to be approached locally. The exploit has been released to the public and may be used for attacks. The patch is identified as 525bf1af642c30af04e4df5345e6d798c0a4d8a1. It is advisable to implement a patch to correct this issue.

Affected products (as reported)

Vendor	Product	Versions
n/a	GPAC	2.02.12.22.32.4.0

Weakness: CWE-476, CWE-404 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C

References

VDB-365629 | GPAC MP4Box isom_intern.c MergeFragment null pointer dereference vdb-entry, technical-description
VDB-365629 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
Submit #816075 | GPAC MP4Box <= 2.4.0 (master commit 7508ccc and earlier) Null pointer dereference (Denial of Service) third-party-advisory
https://github.com/gpac/gpac/issues/3549 issue-tracking
https://github.com/user-attachments/files/27196918/poc.zip exploit
https://github.com/makesoftwaresafe/gpac/commit/525bf1af642c30af04e4df5345e6d798c0a4d8a1 patch
https://github.com/gpac/gpac/ product