CVE-2026-55871 GYM One: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') in admin/users/index.php
An authenticated administrator can inject SQL via search fields to read arbitrary data, including password hashes, and potentially write files.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-55871?
CVE-2026-55871 is a medium-severity SQL injection vulnerability in mayerbalintdev GYM-One, published on 15 Oct 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
GYM One is open-source gym management software for fitness centers, personal trainers, and sports clubs. Prior to 1.4.1, GYM One's admin/users/index.php concatenates the search_name and search_email GET parameters into both the user-list query and the COUNT query used for pagination without prepared statements. An authenticated administrator can inject SQL through either search field to read data from arbitrary tables, including user information and password hashes. Depending on database permissions, the same injection may also permit filesystem writes. This issue is fixed in version 1.4.1.
Weakness: CWE-89
Which versions are affected by CVE-2026-55871?
How do I fix CVE-2026-55871?
No fix has been published for CVE-2026-55871 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-2026-55871 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55871 exists.
Sources
Also known as GHSA-9j4g-cq35-8997.