CVE-2026-18387 Groundhogg <= 4.5.14 - Authenticated (Vendor+) SQL Injection via 'tag_query' Parameter
Authenticated vendors can exploit SQL injection in Groundhogg to extract sensitive database information via the tag_query parameter.
- 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-2026-18387?
CVE-2026-18387 is a medium-severity SQL injection vulnerability in trainingbusinesspros Groundhogg — CRM, Newsletters, and Marketing Automation, published on 15 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The Groundhogg — CRM, Newsletters, and Marketing Automation plugin for WordPress is vulnerable to generic SQL Injection via the 'tag_query' parameter in all versions up to, and including, 4.5.14 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for authenticated attackers, with vendor-level access and above, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database. Exploitation requires the attacker to trigger the vulnerable Legacy_Contact_Query code path by submitting an unknown filter type (e.g. filters[0][0][type]=force_fallback), which causes a FilterException that dispatches execution away from the modern query handler.
Weakness: CWE-89
Which versions are affected by CVE-2026-18387?
How do I fix CVE-2026-18387?
No fix has been published for CVE-2026-18387 yet. Limit exposure of the affected software until one is available.
Use parameterised queries everywhere and never build SQL by joining strings. Upgrade affected software first; a web application firewall only buys time. More about SQL injection.
Is CVE-2026-18387 being exploited?
There is no known exploitation of CVE-2026-18387 in the wild and no public exploit code.
Sources
Also known as GHSA-4mgr-f3j8-4rg7.