CVE-2026-40196

High

Description

HomeBox is a home inventory and organization system. Versions prior to 0.25.0 contain a vulnerability where the defaultGroup ID remained permanently assigned to a user after being invited to a group, even after their access to that group was revoked. While the web interface correctly enforced the access revocation and prevented the user from viewing or modifying the group's contents, the API did not. Because the original group ID persisted as the user's defaultGroup, and this value was not properly validated when the X-Tenant header was omitted, the user could still perform full CRUD operations on the group's collections through the API, bypassing the intended access controls. This issue has been fixed in version 0.25.0.

SeverityHigh
CVSS8.1
Exploit probability—
ProductSysadminsmedia Homebox
PublishedApr 17, 2026
First seenApr 17, 2026
Weakness typeCWE-708CWE-708

How to fix

Update
  • sysadminsmedia homebox0.25.0 or later

Affected products

ProductAffected versionsFixed in
sysadminsmedia homeboxv < 0.25.00.25.0

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