CVE-2026-19856 All in One SEO < 5.0.2.1 - Unauthenticated Arbitrary Shortcode Execution via Search Query
Unauthenticated attackers can execute arbitrary shortcodes in the All in One SEO WordPress plugin, potentially leading to code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-19856?
CVE-2026-19856 is a medium-severity code injection vulnerability in Unknown All in One SEO, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The All in One SEO WordPress plugin before 5.0.2.1 does not correctly determine which shortcodes are present in content derived from user input before deciding which ones to strip, allowing unauthenticated users to execute arbitrary shortcodes registered on the site. On sites upgraded from older versions the protection is disabled outright, making the issue reachable without any crafted input.
Weakness: CWE-74
Which versions are affected by CVE-2026-19856?
How do I fix CVE-2026-19856?
No fix has been published for CVE-2026-19856 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-19856 being exploited?
There is no known exploitation of CVE-2026-19856 in the wild and no public exploit code.
Sources
Also known as GHSA-f9q5-f8p2-3w5w.