CVE-2026-78839

HIGHPre-NVD 8.18.1—
EchelonGraph scoreHIGH confidence

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-09-04. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.1Exploit: None knownExposed: 0

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

An arbitrary file upload vulnerability in AppNitro MachForm v30 allows attackers to execute arbitrary code via uploading a crafted .phar file.

CVSS v3
8.1
EG Score
8.1(high)
EG Risk
37(Track)
EG Risk 37/100SSVC: 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
Severity81% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
43%
KEV
Not listed

Published

September 4, 2026

Last Modified

September 9, 2026

Advisory Details (2)

Auto-updated Sep 9, 2026
No patch confirmed yet.
generic

GitHub - nabeelmkhan/CVE-2026-78839 · GitHub

https://github.com/nabeelmkhan/CVE-2026-78839
generic

Packet Storm Security

https://packetstormsecurity.com

Vendor Advisories for CVE-2026-78839(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 28× in last 7d / 57× 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. 2026-09-21 13:11 UTCGHSA enrichment
  2. 2026-09-21 02:07 UTCEG score recompute
  3. 2026-09-21 02:07 UTCGHSA enrichment
  4. 2026-09-20 20:16 UTCEPSS rescore
  5. 2026-09-20 15:02 UTCGHSA enrichment
  6. 2026-09-20 03:58 UTCGHSA enrichment
  7. 2026-09-19 16:53 UTCEG score recompute
  8. 2026-09-19 16:53 UTCGHSA enrichment
  9. 2026-09-19 05:49 UTCEG score recompute
  10. 2026-09-19 05:48 UTCGHSA enrichment
  11. 2026-09-18 19:28 UTCEPSS rescore
  12. 2026-09-18 18:42 UTCGHSA enrichment
  13. 2026-09-18 07:37 UTCGHSA enrichment
  14. 2026-09-17 20:32 UTCEG score recompute
  15. 2026-09-17 20:32 UTCGHSA enrichment
  16. 2026-09-17 07:24 UTCGHSA enrichment
  17. 2026-09-16 20:19 UTCEG score recompute
  18. 2026-09-16 20:18 UTCGHSA enrichment
  19. 2026-09-16 14:08 UTCEPSS rescore
  20. 2026-09-16 09:11 UTCEG score recompute
  21. 2026-09-16 09:11 UTCGHSA enrichment
  22. 2026-09-16 05:15 UTCEPSS rescore
  23. 2026-09-15 22:05 UTCGHSA enrichment
  24. 2026-09-15 11:00 UTCEG score recompute
  25. 2026-09-15 11:00 UTCGHSA enrichment
Show 32 more
  1. 2026-09-15 03:12 UTCEPSS rescore
  2. 2026-09-15 03:12 UTCEPSS rescore
  3. 2026-09-14 23:32 UTCGHSA enrichment
  4. 2026-09-14 11:53 UTCGHSA enrichment
  5. 2026-09-14 00:48 UTCEG score recompute
  6. 2026-09-14 00:48 UTCGHSA enrichment
  7. 2026-09-13 13:44 UTCGHSA enrichment
  8. 2026-09-13 02:40 UTCGHSA enrichment
  9. 2026-09-12 15:35 UTCEG score recompute
  10. 2026-09-12 15:35 UTCGHSA enrichment
  11. 2026-09-12 04:30 UTCGHSA enrichment
  12. 2026-09-11 17:26 UTCEG score recompute
  13. 2026-09-11 17:26 UTCGHSA enrichment
  14. 2026-09-11 14:53 UTCEPSS rescore
  15. 2026-09-11 14:53 UTCEPSS rescore
  16. 2026-09-11 06:04 UTCGHSA enrichment
  17. 2026-09-10 18:59 UTCEG score recompute
  18. 2026-09-10 18:59 UTCGHSA enrichment
  19. 2026-09-10 07:54 UTCEG score recompute
  20. 2026-09-10 07:54 UTCGHSA enrichment
  21. 2026-09-09 20:49 UTCGHSA enrichment
  22. 2026-09-09 19:46 UTCEG score recompute▲ 8.10
  23. 2026-09-09 19:46 UTCGHSA enrichment
  24. 2026-09-09 19:46 UTCMITRE cvelistV5CVSS v3 → 8.1 · severity → HIGH
  25. 2026-09-08 22:01 UTCEPSS rescore
  26. 2026-09-08 19:59 UTCGHSA enrichment
  27. 2026-09-07 20:15 UTCEG score recompute
  28. 2026-09-07 20:15 UTCGHSA enrichment
  29. 2026-09-06 13:48 UTCEPSS rescore
  30. 2026-09-04 19:18 UTCNVD update
  31. 2026-09-04 18:59 UTCEG score recompute
  32. 2026-09-04 18:59 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-78839?
CVE-2026-78839 is a high vulnerability published on September 4, 2026. An arbitrary file upload vulnerability in AppNitro MachForm v30 allows attackers to execute arbitrary code via uploading a crafted .phar file.
When was CVE-2026-78839 disclosed?
CVE-2026-78839 was first published in the National Vulnerability Database on September 4, 2026, with the most recent update on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-78839 actively exploited?
CVE-2026-78839 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 57.2% of all scored CVEs.
What is the CVSS score of CVE-2026-78839?
CVE-2026-78839 has a CVSS v3.1 base score of 8.1 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-78839?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-78839, 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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