CVE-2026-128240: gpac · Use After Free
Affects gpacSource CVE Database V5
Not known to be exploited · CVSS 6.8 Medium.
Data as of 13 Nov 2026, 09:58 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 6.8 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 5.5 |
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 13 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| gpacgpac | Affected
| Fixed in– |
GitHubgpacpkg:github/gpacOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, avoid processing untrusted or crafted XMT/BT scenes with MP4Box -chap to mitigate risk.
Description
GPAC versions up to and including 26.07.0 contain a use-after-free vulnerability in the function gf_sg_proto_del() within the VRML prototype handling code. This flaw occurs because gf_sg_reset() frees unregistered prototypes that are still referenced by scene commands. An attacker can exploit this by supplying a crafted XMT/BT scene with prototype declarations processed by the MP4Box -chap command, causing the process to access freed memory and crash.
References
- github.com/gpac/gpac/issues/4031 (opens in a new tab)
- github.com/gpac/gpac/commit/a2e5c62c213b5329a4572fe8e7c333e1ca26d028 (opens in a new tab)
- github.com/gpac/gpac/blob/v26.07.0/src/scenegraph/vrml_proto.c (opens in a new tab)
- github.com/gpac/gpac/blob/v26.07.0/src/scenegraph/base_scenegraph.c (opens in a new tab)
- github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/223/223_gf_sg_proto_del_scenegraph_vrml_proto_c.xmt (opens in a new tab)
- github.com/gpac/gpac (opens in a new tab)
- vulncheck.com/advisories/gpac-through-26.07.0-use-after-free-in-gf-sg-proto-del-during-scene-teardown (opens in a new tab)