CVE-2026-12157 BetterDocs <= 4.5.3 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'blockId' Block Attribute
Authenticated contributors can inject arbitrary scripts via the blockId attribute, leading to stored XSS execution for other users.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-12157?
CVE-2026-12157 is a medium-severity cross-site scripting vulnerability in wpdevteam BetterDocs – AI Documentation, Knowledge Base, Docs, Wikis, FAQ with Chatbot, published on 19 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-79
Which versions are affected by CVE-2026-12157?
How do I fix CVE-2026-12157?
No fix has been published for CVE-2026-12157 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-12157 being exploited?
There is no known exploitation of CVE-2026-12157 in the wild and no public exploit code.
Sources
Also known as GHSA-hcf9-p628-6437.