CVE-2026-27821highCWE-121

CVE-2026-27821: high-severity vulnerability in gpac

GPAC NHML Demuxer (dmx_nhml.c) Vulnerable to Stack Buffer Overflow

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.7epss 0.3%
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/dmx_nhml.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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P
Affected products
gpac · gpac
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