CVE-2021-20717Known exploitationNetwork attack vector

Administrator-browser script execution via unescaped order data

Published May 10, 2021 · Updated Aug 3, 2024

Stored cross-site scripting in EC-CUBE 4.0.0 through 4.0.5 allows remote attackers to execute script in an administrator's browser. The order mail-preview template renders form.tpl_data.vars.data through Twig's raw filter, bypassing output escaping for attacker-controlled order fields. An administrator must preview the affected order email; browser-context execution has been used to expose payment-card data.

CVSS severity7.1
High
EPSS probability2.31%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in EC-CUBE 4.0.0 through 4.0.5 allows remote attackers to execute script in an administrator's browser. The order mail-preview template renders form.tpl_data.vars.data through Twig's raw filter, bypassing output escaping for attacker-controlled order fields. An administrator must preview the affected order email; browser-context execution has been used to expose payment-card data.

The record

CVE
CVE-2021-20717
Published
May 10, 2021
Updated
Aug 3, 2024
Vendor
EC-CUBE CO.,LTD.
Product
EC-CUBE
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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=4.0.0 to 4.0.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

EC-CUBE CO.,LTD. · EC-CUBEversion=4.0.0 to 4.0.5

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
7.1JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
6.8JPCERT/CCAV:N/AC:M/Au:N/C:P/I:P/A:P

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 exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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.

Reported exploitation

Technologies

Your stack

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Your stack

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