CVE-2026-27821: GPAC NHML Demuxer (dmx_nhml.c) Vulnerable to Stack Buffer Overflow

Published Feb 26, 2026
·
Updated

GPAC is an open-source multimedia framework. In versions up to and including 26.02.0, a stack buffer overflow occurs during NHML file parsing in src/filters/dmxnhml.c. The value of the xmlHeaderEnd XML attribute is copied from att->value into szXmlHeaderEnd[1000] using strcpy() without any length validation. If the input exceeds 1000 bytes, it overwrites beyond the stack buffer boundary. Commit 9bd7137fded2db40de61a2cf3045812c8741ec52 patches the issue.

Affected Software

2 affected components
Gpac GPAC<=26.02.0
Gpac GPAC<=26.02.0

Event History

Feb 26, 2026
CVE Published
via MITRE·12:08 AM
Data Sourced
via MITRE·12:08 AM
DescriptionWeakness
Data Sourced
via NVD·12:16 AM
RemedyDescriptionSeverityWeaknessAffected Software
Oct 13, 58162
Event
via NVD·12:14 PM

Frequently Asked Questions

1

What is the severity of CVE-2026-27821?

CVE-2026-27821 is classified as a high severity vulnerability due to the potential for a stack buffer overflow.

2

How do I fix CVE-2026-27821?

To fix CVE-2026-27821, update GPAC to version 26.02.1 or later where this vulnerability is addressed.

3

What causes the CVE-2026-27821 vulnerability?

CVE-2026-27821 is caused by a stack buffer overflow during NHML file parsing in GPAC's DMX filter.

4

Which versions of GPAC are affected by CVE-2026-27821?

GPAC versions up to and including 26.02.0 are affected by CVE-2026-27821.

5

What impact does CVE-2026-27821 have on systems?

CVE-2026-27821 can lead to remote code execution or application crashes, compromising system security.

Contact

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