CVSS 4.0
6.8 mediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-128240 GPAC through 26.07.0 Use-After-Free in gf_sg_proto_del During Scene Teardown
Medium (6.8) in gpac gpac. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
On this page
GPAC through 26.07.0 contains a use-after-free vulnerability in gf_sg_proto_del() in src/scenegraph/vrml_proto.c because gf_sg_reset() frees unregistered prototypes still referenced by scene commands. Attackers can supply a crafted XMT/BT scene declaring prototypes via commands, processed by MP4Box -chap, to trigger freed memory access and crash the process.
Severity
CVSS 3.1
5.5 mediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 6th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-416 Use After Free
- Published
- Modified
- Assigned by
- VulnCheck (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| gpac | through 26.07.0 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | Pro:14.04:LTS, Pro:16.04:LTS, Pro:18.04:LTS and 3 more | gpac | no fix listed | UBUNTU-CVE-2026-128240 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.
References
- https://github.com/gpac/gpac
- https://github.com/gpac/gpac/blob/v26.07.0/src/scenegraph/base_scenegraph.c#L537-L542
- https://github.com/gpac/gpac/blob/v26.07.0/src/scenegraph/vrml_proto.c#L103-L111
- https://github.com/gpac/gpac/commit/a2e5c62c213b5329a4572fe8e7c333e1ca26d028
- https://github.com/gpac/gpac/issues/4031
- https://github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/223/223_gf_sg_proto_del_scenegraph_vrml_proto_c.xmt
- https://www.vulncheck.com/advisories/gpac-through-26.07.0-use-after-free-in-gf-sg-proto-del-during-scene-teardown