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TI-2026-22173 Aliases CVE-2026-27821

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

Priority HIGH 73CWE-121Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00324 25th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
gpacgpacup to 26.02.0—No fix listedCNA
  • gpac Vendorgpac Affected up to 26.02.0 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:gpac:gpac:*:*:*:*:*:*:*:*up to 26.02.0Vulnerablegpac
  • cpe:2.3:a:gpac:gpac:*:*:*:*:*:*:*:* Versions up to 26.02.0 Vulnerable ·gpac

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-27821

References

Exploit 1

Patch 1

  • TI-2023-25004 An issue was discovered in gpac version 2.3-DEV-rev588-g7edc40fee-master, allows remote… CVSS 3.1CRITICAL 9.8
  • TI-2025-43085 GPAC v2.4.0 was discovered to contain an out-of-bounds read in the oggdmx_parse_tags function. CVSS 3.1HIGH 8.2
  • TI-2024-00295 Stack-based Buffer Overflow in gpac/gpac CVSS 3.1CRITICAL 9.8
  • TI-2023-25341 Heap Buffer Overflow vulnerability in GPAC version 2.3-DEV-rev617-g671976fcc-master… CVSS 3.1CRITICAL 9.8
  • TI-2023-02661 NULL Pointer Dereference in gpac/gpac CVSS 3.1CRITICAL 9.8
  • TI-2023-25003 Heap-based Buffer Overflow vulnerability in gpac version… CVSS 3.1HIGH 8.8
See all 400 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences