CVE-2026-55872

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.

• CWE-79

• https://github.com/mayerbalintdev/GYM-One/commit/d3a0cf134f0ab3ac12aee7dca283b93c4290dcc4
• https://github.com/mayerbalintdev/GYM-One/releases/tag/V1.4.1
• https://github.com/mayerbalintdev/GYM-One/security/advisories/GHSA-75g9-vp9w-5388
• https://github.com/mayerbalintdev/GYM-One/security/advisories/GHSA-75g9-vp9w-5388

Published

Oct 15, 2026

Last Modified

Oct 21, 2026

Status

Deferred

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-55865Python Liquid is a Python engine for the Liquid template lan…7.1
• CVE-2026-55866SpiceDB is an open source database system for creating and m…3.7
• CVE-2026-55867Graylog is a free and open log management platform. From 6.2…5.3
• CVE-2026-5587A vulnerability was identified in wbbeyourself MAC-SQL up to…6.3
• CVE-2026-55870GoCD is a continuous deliver server. Prior to 26.1.0, GoCD c…2.3
• CVE-2026-55871GYM One is open-source gym management software for fitness c…6.5
• CVE-2026-55873SeaweedFS is a distributed storage system. In versions 4.08 …4.3
• CVE-2026-55874SeaweedFS is a distributed storage system. Prior to 4.34, th…7.7
• CVE-2026-55875Helium is a free online student planner for classes, homewor…4.3
• CVE-2026-55876Helium is a free online student planner for classes, homewor…3.5
• CVE-2026-55877Symfony UX is a JavaScript ecosystem for Symfony. From 2.17.…6.1
• CVE-2026-55878Symfony UX is a JavaScript ecosystem for Symfony. From 2.32.…7.8