CVE-2026-91819: Affected versions of MISP rely on CakePHP request-method override processing in a way that can disable CSRF and form-security validation.

Affected versions of MISP rely on CakePHP request-method override processing in a way that can disable CSRF and form-security validation.

Affected versions of MISP rely on CakePHP request-method override processing in a way that can disable CSRF and form-security validation. CakePHP honors a _method field or X-HTTP-Method-Override header by rewriting the effective request method. For override values outside the normal write verbs POST, PUT, PATCH, and DELETE, CakePHP also clears the parsed request body. MISP’s security component then determines whether to perform _validatePost() and _validateCsrf() based on whether request data remains. With a value such as: _method=GET the body becomes empty before those checks run, so both protections are skipped. A cross-site form containing only that override can therefore reach actions whose parameters are taken from the URL rather than the request body Version affected: ≤2.5.45

Description from the National Vulnerability Database, published by 5a6e4751-2f3f-4070-9419-94fb35b644e8

What it means for a small business

If your business uses MISP, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.20%, higher than 9% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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