CVE-2021-22122 Exploited in the Wild — Fortinet FortiWeb

Vendor	Product	Version	Status
Fortinet	Fortinet FortiWeb	FortiWeb 6.3.0 through 6.3.7 and version before 6.2.4	Affected

Known Exploited Vulnerability Sources

Catalogues that list this CVE as a known exploited vulnerability.

Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.

Source	Added
The Shadowserver First	2025-12-28 00:00 UTC

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner	Reference	Detected
Nuclei	https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-22122.yaml	Apr 25, 2025

Virtual Patch

Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.

Not available

KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.

Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.

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CVSS Scores

CVSS v3.1 6.1 Medium

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS v2.0 4.3 Medium

AV:N/AC:M/Au:N/C:N/I:P/A:N

Exploitation Status

Exploited in the wild

Recorded 2025-12-28 00:00:00 UTC · The Shadowserver

Proof of concept available

Recorded 2026-06-12 14:20:19 UTC · Nuclei Templates

Weaknesses (CWE)

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Scanner Integrations

Nuclei, Metasploit, and other scanner references for this CVE are listed on the Detection tab.

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

FortiWeb - Cross Site Scripting

nuclei · Created Unknown

Timeline

Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.

12 Jun 2026 14:20 UTC about 2 months ago

12 Jun 2026 14:20 UTC · about 2 months ago

Public PoC available

Public proof-of-concept code published
28 Dec 2025 00:00 UTC 7 months ago

28 Dec 2025 00:00 UTC · 7 months ago

Added to KEVIntel KEV Feed

High-confidence, third-party attested exploitation
25 Apr 2025 00:00 UTC over 1 year ago

25 Apr 2025 00:00 UTC · over 1 year ago

Nuclei template available

Scanner coverage available
8 Feb 2021 15:55 UTC over 5 years ago

8 Feb 2021 15:55 UTC · over 5 years ago

CVE published

Vulnerability disclosed publicly
4 Jan 2021 00:00 UTC over 5 years ago

4 Jan 2021 00:00 UTC · over 5 years ago

CVE ID reserved

Identifier reserved by the CNA

Automate This Intelligence with the Pro API

Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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Pro API Example

GET /api/v2/pro/kevs/CVE-2021-22122

{
  "cve_id": "CVE-2021-22122",
  "title": "An improper neutralization of input during web page generation in FortiWeb GU...",
  "affected_vendor": "Fortinet",
  "affected_product": "Fortinet FortiWeb",
  "affected_versions": [
    { "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
  ],
  "confidence": "High",
  "cvss_score": 6.1,
  "epss_score": 0.1052,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "...": "Pro API fields" },
  "proof_of_concepts": [ "..." ],
  "scanner_integrations": [ "..." ]
}

The free JSON API returns basic KEV fields only. Confidence, telemetry, and artifact enrichment require Pro API access.

CVE-2021-22122

At a Glance

Affected Versions

CVE References