CVE-2024-3866Network attack vector

Browser script execution via unescaped Referer header

Published Sep 25, 2024 · Updated Apr 8, 2026

Reflected self-XSS in Saturday Drive Ninja Forms 3.8.15 and earlier allows remote attackers to run scripts via a crafted Referer header. The maintenance-mode response inserts the request's Referer value into generated HTML without sufficient sanitization or output escaping. The form must briefly enter maintenance mode during a required update, and a targeted user must be induced to issue the request; script execution occurs in that user's browser under the site's origin.

CVSS severity4.7
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected self-XSS in Saturday Drive Ninja Forms 3.8.15 and earlier allows remote attackers to run scripts via a crafted Referer header. The maintenance-mode response inserts the request's Referer value into generated HTML without sufficient sanitization or output escaping. The form must briefly enter maintenance mode during a required update, and a targeted user must be induced to issue the request; script execution occurs in that user's browser under the site's origin.

The record

CVE
CVE-2024-3866
Published
Sep 25, 2024
Updated
Apr 8, 2026
Vendor
Saturday Drive
Product
Ninja Forms
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 25, 2024CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=3.8.15

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Saturday Drive · Ninja Formsversion=0 <=3.8.15

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
4.7WordfenceCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001Malicious Link

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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