CVE-2026-27821

HIGHNVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.8 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 81% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
7.8
EG Score
7.8(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity78% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
20%
KEV
Not listed

Published

February 26, 2026

Last Modified

June 17, 2026

Advisory Details (2)

Auto-updated Aug 2, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github.
github Patch Available🟡 PoC Available

Stack Buffer Overflow in GPAC NHML Demuxer (dmx_nhml.c) · Advisory · gpac/gpac · GitHub

https://github.com/gpac/gpac/security/advisories/GHSA-q7qh-8r2r-q559
github_commit Patch Available

commit 9bd7137fded2 (gpac/gpac)

Patch available: gpac/gpac v26.07.0 (contains commit 9bd7137fded2)

https://github.com/gpac/gpac/commit/9bd7137fded2db40de61a2cf3045812c8741ec52

Affected Packages

(1 across 1 ecosystem)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
gpac1.0.1+dfsg1-4 ... 2.2.1+dfsg1-3.1~exp1 (13 versions)——

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 28× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 13:02 UTCOSV refresh
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 19:27 UTCEPSS rescore
  4. 2026-09-17 19:30 UTCEPSS rescore
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-13 16:47 UTCEPSS rescore
  8. 2026-09-12 15:01 UTCEPSS rescore
  9. 2026-09-11 14:52 UTCEPSS rescore
  10. 2026-09-10 09:34 UTCEPSS rescore
  11. 2026-09-08 22:00 UTCEPSS rescore
  12. 2026-09-07 16:01 UTCEPSS rescore
  13. 2026-09-06 13:47 UTCEPSS rescore
  14. 2026-09-06 13:47 UTCEPSS rescore
  15. 2026-09-04 05:06 UTCEPSS rescore
  16. 2026-09-02 14:11 UTCEPSS rescore
  17. 2026-09-01 13:53 UTCEPSS rescore
  18. 2026-09-01 04:39 UTCEPSS rescore
  19. 2026-09-01 04:39 UTCEPSS rescore
  20. 2026-08-31 16:34 UTCOSV refresh
  21. 2026-08-30 19:17 UTCEPSS rescore
  22. 2026-08-30 01:22 UTCEPSS rescore
  23. 2026-08-28 21:41 UTCEPSS rescore
  24. 2026-08-27 14:25 UTCEPSS rescore
  25. 2026-08-26 14:46 UTCEPSS rescore
Show 36 more
  1. 2026-08-25 13:48 UTCEPSS rescore
  2. 2026-08-23 00:19 UTCEPSS rescore
  3. 2026-08-21 23:49 UTCEPSS rescore
  4. 2026-08-20 22:55 UTCEPSS rescore
  5. 2026-08-19 17:03 UTCEPSS rescore
  6. 2026-08-18 13:48 UTCEPSS rescore
  7. 2026-08-17 13:47 UTCEPSS rescore
  8. 2026-08-16 14:56 UTCEPSS rescore
  9. 2026-08-16 02:14 UTCEPSS rescore
  10. 2026-08-15 01:30 UTCEPSS rescore
  11. 2026-08-14 08:58 UTCEG score recompute
  12. 2026-08-13 22:00 UTCEPSS rescore
  13. 2026-08-13 00:57 UTCEG score recompute
  14. 2026-08-12 13:50 UTCEPSS rescore
  15. 2026-08-11 23:53 UTCEG score recompute
  16. 2026-08-11 13:42 UTCEPSS rescore
  17. 2026-08-11 06:17 UTCEG score recompute
  18. 2026-08-11 00:00 UTCEPSS rescore
  19. 2026-08-09 20:38 UTCEG score recompute
  20. 2026-08-09 13:46 UTCEPSS rescore
  21. 2026-08-09 08:35 UTCEG score recompute
  22. 2026-08-08 16:37 UTCEPSS rescore
  23. 2026-08-07 20:38 UTCEG score recompute
  24. 2026-08-06 13:46 UTCEPSS rescore
  25. 2026-08-06 02:59 UTCEG score recompute
  26. 2026-08-05 19:17 UTCEPSS rescore
  27. 2026-08-04 15:10 UTCEPSS rescore
  28. 2026-08-04 05:48 UTCEG score recompute
  29. 2026-08-03 10:36 UTCEPSS rescore
  30. 2026-08-02 19:30 UTCEG score recompute
  31. 2026-08-02 02:26 UTCEPSS rescore
  32. 2026-08-01 04:16 UTCEPSS rescore
  33. 2026-07-30 16:27 UTCEPSS rescore
  34. 2026-07-30 01:30 UTCEPSS rescore
  35. 2026-07-28 15:36 UTCEPSS rescore
  36. 2026-07-27 13:34 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-27821?
CVE-2026-27821 is a high vulnerability published on February 26, 2026. 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…
When was CVE-2026-27821 disclosed?
CVE-2026-27821 was first published in the National Vulnerability Database on February 26, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-27821 actively exploited?
CVE-2026-27821 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 80.2% of all scored CVEs.
What is the CVSS score of CVE-2026-27821?
CVE-2026-27821 has a CVSS v3 base score of 7.8 (NVD).
How do I remediate CVE-2026-27821?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-27821, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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