CVE-2026-33144 GPAC MP4Box Heap Buffer Overflow Write in gf_xml_parse_bit_sequence_bs (NHML BS Parsing)
A heap buffer overflow in GPAC MP4Box allows attackers to execute arbitrary code or cause denial of service via crafted NHML files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-33144?
CVE-2026-33144 is a medium-severity memory corruption vulnerability in Gpac Gpac, published on 20 Mar 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
GPAC is an open-source multimedia framework. Prior to commit 86b0e36, a heap-based buffer overflow (write) vulnerability was discovered in GPAC MP4Box. The vulnerability exists in the gf_xml_parse_bit_sequence_bs function in utils/xml_bin_custom.c when processing a crafted NHML file containing malicious <BS> (BitSequence) elements. An attacker can exploit this by providing a specially crafted NHML file, causing an out-of-bounds write on the heap. This issue has been via commit 86b0e36.
Weakness: CWE-787
Which versions are affected by CVE-2026-33144?
It affects 1 product.
Products include Gpac Gpac.
How do I fix CVE-2026-33144?
No fix has been published for CVE-2026-33144 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-33144 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33144 exists.
Other vulnerabilities in Gpac Gpac
Sources
Also known as DEBIAN-CVE-2026-33144, GHSA-3jw5-9pmw-vmfg, UBUNTU-CVE-2026-33144.