CVE-2021-3378

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 97.5%, top 0% 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
Weaponized
9.8
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 98%
CISA-KEV: Not listedEPSS: 98%CVSS: 9.8Exploit: NoneExposed: 0

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

FortiLogger 4.4.2.2 is affected by Arbitrary File Upload by sending a "Content-Type: image/png" header to Config/SaveUploadedHotspotLogoFile and then visiting Assets/temp/hotspot/img/logohotspot.asp.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
88(Track*)
EG Risk 88/100SSVC: 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
Severity98% × 45%
Exploitation98% × 40%
Automatability30% × 15%
Action: Watch closely — could escalate to Attend.
EPSS
99.9%
KEV
Not listed

Published

February 1, 2021

Last Modified

November 21, 2024

Advisory Details (2)

Auto-updated Jul 1, 2026
No patch confirmed yet.
generic

GitHub - erberkan/fortilogger_arbitrary_fileupload: CVE-2021-3378 | FortiLogger - Unauthenticated Arbitrary File Upload (Metasploit) · GitHub

https://github.com/erberkan/fortilogger_arbitrary_fileupload
generic

Packet Storm

http://packetstormsecurity.com/files/161974/FortiLogger-Arbitrary-File-Upload.html

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 3× in last 7d / 11× 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. 2026-07-23 02:01 UTCEG score recompute
  2. 2026-07-22 22:48 UTCEG score recompute
  3. 2026-07-20 17:05 UTCEPSS rescore
  4. 2026-07-08 15:12 UTCEPSS rescore
  5. 2026-07-05 02:28 UTCEPSS rescore
  6. 2026-07-05 02:28 UTCEPSS rescore
  7. 2026-07-01 15:04 UTCEPSS rescore
  8. 2026-06-30 23:20 UTCEPSS rescore
  9. 2026-06-30 23:20 UTCEPSS rescore
  10. 2026-06-28 04:54 UTCEPSS rescore
  11. 2026-06-28 04:54 UTCEPSS rescore
  12. 2026-06-23 21:31 UTCEPSS rescore
  13. 2026-06-23 21:31 UTCEPSS rescore
  14. 2026-06-15 17:46 UTCEPSS rescore
  15. 2026-06-14 23:15 UTCEPSS rescore
  16. 2026-06-14 23:15 UTCEPSS rescore
  17. 2026-06-10 13:20 UTCEPSS rescore
  18. 2026-06-06 13:46 UTCEPSS rescore
  19. 2026-06-06 13:46 UTCEPSS rescore
  20. 2026-06-05 22:45 UTCEPSS rescore
  21. 2026-06-02 20:11 UTCEPSS rescore
  22. 2026-06-02 20:11 UTCEPSS rescore
  23. 2026-06-01 13:50 UTCEPSS rescore
  24. 2026-06-01 13:50 UTCEPSS rescore
  25. 2026-05-29 13:42 UTCEPSS rescore
Show 7 more
  1. 2026-05-27 13:39 UTCEPSS rescore
  2. 2026-05-27 13:39 UTCEPSS rescore
  3. 2026-05-26 07:17 UTCEPSS rescore
  4. 2026-05-26 07:17 UTCEPSS rescore
  5. 2026-05-26 07:17 UTCEPSS rescore
  6. 2026-05-23 07:56 UTCEG score recompute
  7. 2026-05-23 07:56 UTCGHSA enrichment

Publicly available exploits

(4 references)

Working exploit code is in the public domain (1 Metasploit module) (1 GitHub PoC) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Exploit-DBEDB-49600✓ verified
    First seen Mar 1, 2021

    FortiLogger 4.4.2.2 - Unauthenticated Arbitrary File Upload (Metasploit)

    Open source ↗
  • Metasploitexploit/windows/http/fortilogger_arbitrary_fileupload✓ verified
    First seen Feb 26, 2021

    FortiLogger Arbitrary File Upload Exploit

    Open source ↗
  • GitHub PoCerberkan/fortilogger_arbitrary_fileupload
    First seen Jan 30, 2021

    CVE-2021-3378 | FortiLogger - Unauthenticated Arbitrary File Upload (Metasploit)

    Open source ↗
  • Nucleihttp/cves/2021/CVE-2021-3378.yaml
    First seen Jan 1, 2021

    FortiLogger 4.4.2.2 - Arbitrary File Upload

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2021-3378?
CVE-2021-3378 is a critical vulnerability published on February 1, 2021. FortiLogger 4.4.2.2 is affected by Arbitrary File Upload by sending a "Content-Type: image/png" header to Config/SaveUploadedHotspotLogoFile and then visiting Assets/temp/hotspot/img/logohotspot.asp.
When was CVE-2021-3378 disclosed?
CVE-2021-3378 was first published in the National Vulnerability Database on February 1, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-3378 actively exploited?
CVE-2021-3378 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-3378?
CVE-2021-3378 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2021-3378?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-3378, 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

Explore the affected products and dependency analysis for CVE-2021-3378

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