{"affected":[{"defaultStatus":"unaffected","ecosystem":"github","packageName":"gpac/gpac","product":"gpac","source":"CNA: VulnCheck","vendor":"gpac","versions":[{"lessThanOrEqual":"26.07.0","status":"affected","version":"0","versionType":"custom"}]}],"cveId":"CVE-2026-128239","cwes":["CWE-476"],"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.","epss":null,"exploits":[{"kind":"exploit","source":"CNA: VulnCheck","url":"https://github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/221/221_ab_apply_compositor_mpeg4_form_c_627.xmt"}],"kev":null,"metrics":[{"score":6.8,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"},{"score":5.5,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","version":"3.1"},{"score":6.8,"severity":"medium","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","version":"4.0"},{"score":5.5,"severity":"medium","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","version":"3.1"}],"modifiedAt":1794565091797,"publishedAt":1794562427579,"references":[{"source":"CNA: VulnCheck","tags":["issue-tracking"],"url":"https://github.com/gpac/gpac/issues/4029"},{"source":"CNA: VulnCheck","tags":["patch"],"url":"https://github.com/gpac/gpac/commit/bc416b997622e43de65afab3bae9b7d05d72f2b0"},{"source":"CNA: VulnCheck","tags":["technical-description"],"url":"https://github.com/gpac/gpac/blob/v26.07.0/src/compositor/mpeg4_form.c#L620-L621"},{"source":"CNA: VulnCheck","tags":["exploit"],"url":"https://github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/221/221_ab_apply_compositor_mpeg4_form_c_627.xmt"},{"source":"CNA: VulnCheck","tags":["product"],"url":"https://github.com/gpac/gpac"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/gpac-through-26.07.0-null-pointer-dereference-via-mpeg-4-form-handlers"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/gpac/gpac"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/gpac/gpac/blob/v26.07.0/src/compositor/mpeg4_form.c#L620-L621"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/gpac/gpac/commit/bc416b997622e43de65afab3bae9b7d05d72f2b0"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/gpac/gpac/issues/4029"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/221/221_ab_apply_compositor_mpeg4_form_c_627.xmt"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://www.vulncheck.com/advisories/gpac-through-26.07.0-null-pointer-dereference-via-mpeg-4-form-handlers"}],"remediation":[{"kind":"fix","source":"CNA: VulnCheck","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/gpac/gpac/commit/bc416b997622e43de65afab3bae9b7d05d72f2b0"}],"revision":"ed5af9a5086f7d861b38d670280c5c223993a463885e24c899c17965c582a16b","sources":[{"modifiedAt":1794562427579,"name":"CNA: VulnCheck","retrievedAt":1794564851621,"url":"https://www.cve.org/CVERecord?id=CVE-2026-128239"},{"modifiedAt":1794565091797,"name":"NVD","retrievedAt":1794572256087,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-128239"}],"ssvc":null,"status":"published","title":"GPAC through 26.07.0 NULL Pointer Dereference via MPEG-4 Form Handlers","updatedAt":1794572256087}