CVE-2026-128239
MEDIUM
NVD
CVSS Score
5.5
Severity
MEDIUM
Published
Nov 13, 2026
Vendor
unknown
Description
GPAC through 26.07.0 contains a NULL pointer dereference vulnerability in the MPEG-4 Form spatial-constraint handlers in src/compositor/mpeg4_form.c that lets attackers crash the process via unchecked group lookups. Attackers can supply a crafted XMT scene whose Form constraints reference a non-existent group, crashing tools like MP4Box during chapter import for denial of service.
References
- https://github.com/gpac/gpac
- https://github.com/gpac/gpac/blob/v26.07.0/src/compositor/mpeg4_form.c#L620-L621
- https://github.com/gpac/gpac/commit/bc416b997622e43de65afab3bae9b7d05d72f2b0
- https://github.com/gpac/gpac/issues/4029
- https://github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/221/221_ab_apply_compositor_mpeg4_form_c_627.xmt