dbcve.org
Cross-site Scripting (XSS)Weakness · CWE-79

CVE-2026-12157

MEDIUM · 6.4 CVSS v3.1 Published 2026-06-19
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
70/100
Remediation priority · Elevated
Remotely reachable Zero-click

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 · unedited
The BetterDocs - Knowledge Base Docs & FAQ Solution for Elementor & Block Editor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the blockId attribute of the betterdocs/category-slate-layout Gutenberg block in versions up to, and including, 4.5.3. This is due to insufficient input sanitization and output escaping in the CategorySlateLayout::render() method, which echoes the blockId block attribute directly into an HTML class attribute without esc_attr(). This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

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 confidence

Stored XSS vulnerability in the BetterDocs WordPress plugin where the blockId attribute from the betterdocs/category-slate-layout Gutenberg block is directly echoed into an HTML class attribute without esc_attr() escaping, allowing authenticated contributor+ users to inject malicious scripts.

MitigationApply esc_attr() to the blockId parameter in the CategorySlateLayout::render() method before output, and update to version 4.5.4 or later when released.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS 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
None
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify BetterDocs plugin installation and version
    Navigate to Plugins > Installed Plugins in WordPress admin, locate BetterDocs, and note the version number displayed
    Affected if The installed version is lower than 4.5.4 (or if version is not displayed, the plugin is likely vulnerable)
  2. Check for Gutenberg block usage
    Edit a post or page and examine whether the betterdocs/category-slate-layout block is present in the editor
    Affected if The category-slate-layout block is being used on any published content
  3. Inspect block configuration for blockId attribute
    In the block editor, select the category-slate-layout block and check the block settings panel (usually in the right sidebar) for a blockId field
    Affected if A custom blockId value is set in the block settings
  4. Examine rendered HTML output
    View the source of a page containing the category-slate-layout block and search for the blockId value within the element's class attribute
    Affected if The blockId value appears unescaped in the HTML class attribute (e.g., class="...blockId-value...")

You are affected if BetterDocs plugin version is below 4.5.4 AND the category-slate-layout Gutenberg block with a custom blockId is in use on your site.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply esc_attr() to the blockId parameter in the CategorySlateLayout::render() method before output, and update to version 4.5.4 or later when released.

Recommended fix Moderate confidence

Version 4.5.4 or later (check WordPress plugin repository for latest stable release)

  1. 1. Navigate to the WordPress admin dashboard
  2. 2. Go to Plugins > Installed Plugins
  3. 3. Locate the BetterDocs plugin
  4. 4. Check the current version number displayed in the plugin list
  5. 5. If the installed version is 4.5.3 or lower, navigate to Plugins > Add New > Upload Plugin or check for an update
  6. 6. Update to the latest available version of BetterDocs that includes the security fix
  7. 7. Verify the update was successful by confirming the new version number
  8. 8. Test that the category-slate-layout block functions correctly after the update

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-12157 in production — separate from our analysis above.

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What this is

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What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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