CVE-2021-3378

Status: ModifiedCritical (9.8)—💥 Exploit

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

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Base score: 9.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 98%
Percentile among all scored CVEs: 100
Score date: 10/2/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

💥 Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

Metasploit module (reliable, widely available exploit) · FortiLogger Arbitrary File Upload Exploit
Published on Exploit-DB · FortiLogger 4.4.2.2 - Unauthenticated Arbitrary File Upload (Metasploit) (3/1/2021)
Nuclei template (automated mass detection) · FortiLogger 4.4.2.2 - Arbitrary File Upload
Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (1)

Fortilogger — Fortilogger

CWEs

CWE-434

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2021-3378",
  "cveTags": [],
  "metrics": {
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        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
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          "baseScore": 7.5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 6.4,
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        "obtainAllPrivilege": false,
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          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
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  "affected": [
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  "published": "2021-02-01T23:15:12.797",
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-434"
        }
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  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    },
    {
      "lang": "es",
      "value": "FortiLogger versión 4.4.2.2, está afectado por una carga arbitraria de archivos mediante el envío de un encabezado \"Content-Type:image/png\" hacia Config/SaveUploadedHotspotLogoFile y luego al visitar el archivo Assets/temp/hotspot/img/logohotspot.asp"
    }
  ],
  "lastModified": "2026-06-17T04:05:00.340",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
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  "sourceIdentifier": "cve@mitre.org"
}