CVE-2021-39308Network attack vector

Reflected XSS via unescaped clientref output

Published Dec 14, 2021 · Updated Jan 31, 2025

Reflected XSS in myghpay WooCommerce Payment Gateway 3.0 and earlier allows remote attackers to run scripts through clientref. The processresponse.php endpoint inserts the clientref request value into its HTML response without output encoding, causing browser markup to be interpreted rather than displayed as data. Exploitation requires a victim to open a crafted response URL, enabling script execution in the site's security context without authentication.

CVSS severity6.1
Medium
EPSS probability0.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in myghpay WooCommerce Payment Gateway 3.0 and earlier allows remote attackers to run scripts through clientref. The processresponse.php endpoint inserts the clientref request value into its HTML response without output encoding, causing browser markup to be interpreted rather than displayed as data. Exploitation requires a victim to open a crafted response URL, enabling script execution in the site's security context without authentication.

The record

CVE
CVE-2021-39308
Published
Dec 14, 2021
Updated
Jan 31, 2025
Vendor
Emmanuel Adu-Asare
Product
myghpay WooCommerce Payment Gateway
Classifications
CWE-79
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 14, 2021CVE publishedPublication date reported by the CVE source.
  2. Jan 31, 2025Record 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=3.0 <=3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Emmanuel Adu-Asare · myghpay WooCommerce Payment Gatewayversion=3.0 <=3.0

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1WordfenceCVSS:3.1/AV:N/AC:L/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')

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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