What is CVE-2026-124031?

CVE-2026-124031 is a medium-severity vulnerability in Gpac, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 5.5/10. Published 2026-11-06.

How severe is CVE-2026-124031?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Vulnerability in Gpac

CVE-2026-124031

GPAC through 26.07.0 contains a type confusion vulnerability in drawable_get_aspect_2d_mpeg4() and TraverseShape() that casts a Shape's appearance node to M_Appearance without checking its node tag. Attackers can supply a crafted XMT file placing another node type, such as Conditional, in the appearance field to trigger an invalid memory read and crash MP4Box.

Published 2026-11-06 · last modified 2026-11-06.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Gpac

Weakness classification (CWE)

CWE-843 — Access of Resource Using Incompatible Type (Type Confusion)

References

github.com/gpac/gpac (product)
github.com/gpac/gpac/blob/v26.07.0/src/compositor/drawable.c (technical-description)
github.com/gpac/gpac/commit/43a8329a90ae2907716b593cc3746458516c7c39 (patch)
github.com/gpac/gpac/issues/4030 (issue-tracking)
github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/222/222_gf_node_get_tag_comp… (exploit)
www.vulncheck.com/advisories/gpac-through-26.07.0-type-confusion-via-drawable-g… (third-party-advisory)

Frequently asked questions

What is CVE-2026-124031?: CVE-2026-124031 is a medium-severity vulnerability in Gpac, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 5.5/10. Published 2026-11-06.
How severe is CVE-2026-124031?: Medium severity. CVSS v3 base score is 5.5 out of 10.