CVE-2026-55872: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in mayerbalintdev GYM-One
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 renders the stored firstname, lastname, and email profile fields into the administrator user list without HTML output encoding. An attacker who can store values in those fields can cause content to execute in an administrator's browser when the administrator visits /admin/users/. The persistent script can access administrator-session data or perform actions with the administrator's privileges until the stored record is removed. This issue is fixed in version 1.4.1.
CVSS v3.1
Score 8.7high
Affected software
mayerbalintdev
GYM-One
Weaknesses
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-17T16:44:40.996Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ad120372cdf04f656517bc1
Added to database: 10/15/2026, 18:49:27 UTC
Last updated: 10/15/2026, 18:49:27 UTC
Views: 1
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