CVE-2021-20742
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedCross-site scripting vulnerability in EC-CUBE Business form output plugin (for EC-CUBE 3.0 series) versions prior to version 1.0.1 allows a remote attacker to inject an arbitrary script via unspecified vector.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceCross-site scripting vulnerability in the EC-CUBE Business form output plugin for EC-CUBE 3.0 series (versions prior to 1.0.1) allows remote attackers to inject arbitrary JavaScript through form fields that are rendered without proper output encoding. This is a stored XSS vulnerability where malicious payloads persist in the application and execute when other users view the affected form output.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 1.0.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Confirm EC-CUBE 3.0 series installationLocate the EC-CUBE installation directory and check the version file or database version record. Look for version 3.0.x indicators in config files or the database.Affected if EC-CUBE 3.0 series is not installed or not the target version range
-
Identify Business Form Output pluginCheck the plugin directory (typically /html/plugin/ or similar) or query the plugin table in the database for an entry named 'Business Form Output' or similar business form plugin.Affected if The Business Form Output plugin is not installed
-
Check plugin versionExamine the plugin's version.php or plugin info file within the plugin directory, or query the plugin version from the database plugin records.Affected if The plugin version is below 1.0.1 (for example, 1.0.0 or any version prior to 1.0.1)
-
Verify plugin is enabledCheck the plugin status in the EC-CUBE admin panel under plugin management, or query the plugin database table for an 'enable' or 'del_flg' flag indicating the plugin is active.Affected if The plugin is installed but disabled (the vulnerability only applies when the plugin is active)
-
Confirm form output functionality is in useCheck if any forms created with the Business Form Output plugin have saved data, or verify that form output templates are being rendered on the storefront or admin pages.Affected if The plugin has no active forms or saved data, the stored XSS cannot be triggered even if the vulnerable version is installed
The environment is affected if EC-CUBE 3.0 series is running with the Business Form Output plugin installed and enabled at a version prior to 1.0.1, and the plugin's form functionality is actively used or accessible.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor data1.0.1
Upgrade the EC-CUBE Business form output plugin to version 1.0.1 or later. If upgrading is not immediately feasible, implement output encoding/sanitization on all form field outputs and apply Content-Security-Policy headers to mitigate XSS execution.
- Consultation3.0 h
- Implementation6.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,224.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-20742 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-20742 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data