CVE-2026-21290
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 · uneditedAdobe Commerce versions 2.4.9-alpha3, 2.4.8-p3, 2.4.7-p8, 2.4.6-p13, 2.4.5-p15, 2.4.4-p16 and earlier are affected by a stored Cross-Site Scripting (XSS) vulnerability that could be abused by a low-privileged attacker to inject malicious scripts into vulnerable form fields. Malicious JavaScript may be executed in a victim’s browser when they browse to the page containing the vulnerable field. A successful attacker can abuse this to achieve session takeover, increasing the confidentiality, and integrity impact to high. Exploitation of this issue requires user interaction in that a victim must browse to the page containing the vulnerable field.
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 · moderate confidenceStored Cross-Site Scripting (XSS) vulnerability in Adobe Commerce allows low-privileged authenticated users to inject malicious JavaScript into vulnerable form fields. When other users browse to pages containing these fields, the injected scripts execute in their browsers, potentially enabling session hijacking and full account takeover.
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< 1.3.3= 1.3.3= 1.3.4= 1.3.5= 1.4.2= 1.5.2= 1.5.3< 2.4.4= 2.4.4= 2.4.5= 2.4.6= 2.4.7= 2.4.8= 2.4.9< 2.4.5= 2.4.5= 2.4.6= 2.4.7= 2.4.8= 2.4.9CVSS 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
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/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.
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Identify installed Adobe Commerce or Magento versionRun command: bin/magento --version or check composer.json for 'version' field under 'magento/product-enterprise-edition' or 'magento/product-community-edition'Affected if Version matches the affected ranges: Adobe Commerce < 2.4.4, = 2.4.4 through = 2.4.9; Magento < 2.4.5, = 2.4.5 through = 2.4.9; or Adobe Commerce B2b < 1.3.3, = 1.3.3 through = 1.3.5, = 1.4.2, = 1.5.2, = 1.5.3
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Check for B2B module installationRun: bin/magento module:status Magento_Company_B2B or inspect app/etc/config.php for 'Magento_Company' module entryAffected if Adobe Commerce B2B module is enabled and version falls within the affected B2b version list
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Verify low-privileged user registration is enabledCheck configuration at Stores > Configuration > Customers > Customer Configuration > Account Sharing Options > 'Share Customer Accounts' set to 'Per Website' or 'Global', or inspect core_config_data table for 'customer/account_share/scope' valueAffected if Low-privileged (non-admin) user registration or access is permitted, enabling the attack vector
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Inspect custom form field handlers for input sanitizationReview code in vendor/magento/module-customer (or custom modules) for form controllers handling user input; look for absence of $this->escaper->escapeHtml() or strip_tags() on form field values before savingAffected if Form handlers save user input without proper HTML encoding or input sanitization
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Examine stored form data for malicious payloadsQuery database: SELECT * FROM customer_address_entity_text WHERE value LIKE '%<script%' OR value LIKE '%javascript:%' OR value LIKE '%onload=%' (or equivalent tables for custom forms)Affected if Stored records contain unsanitized HTML or JavaScript event handlers that could execute in another user's browser
User is affected if running any Adobe Commerce or Magento version within the listed affected ranges AND low-privileged authenticated users can submit form data that is stored without proper HTML encoding.
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.
dbcve · scoped1.3.32.4.42.4.5
Upgrade Adobe Commerce to patched versions (2.4.4-p17, 2.4.5-p16, 2.4.6-p14, 2.4.7-p9, 2.4.8-p4 or later) that address this stored XSS vulnerability.
Adobe Commerce 2.4.9 (stable) or latest 2.4.x patch version (e.g., 2.4.9-p1) | Adobe Commerce B2b 1.3.6+ | For older branches: 2.4.8-p4+, 2.4.7-p9+, 2.4.6-p14+, 2.4.5-p16+, 2.4.4-p17+
- 1. Identify the current Adobe Commerce/Magento version by running: php bin/magento --version
- 2. Determine the appropriate upgrade path based on current version (see upgrade_path)
- 3. Create a full backup of the database and files before upgrading
- 4. Enable maintenance mode: php bin/magento maintenance:enable
- 5. Run composer to update the Magento core package: composer require magento/product-community-edition=<target-version> --no-update
- 6. Update composer dependencies: composer update
- 7. Clear the cache and regenerate static content: rm -rf var/cache var/generation pub/static/* && php bin/magento setup:upgrade
- 8. Compile di and deploy static content if needed: php bin/magento setup:di:compile && php bin/magento setup:static-content:deploy
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing6.0 h
- Review / QA3.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-21290 — 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-2026-21290 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
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- 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
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