CVE-2026-40196

HomeBox has Unauthorized API Access via Retained defaultGroup ID After Group Access Revocation

HIGH
8.1
CVSS Score
Published: April 17, 2026 at 09:01 PM UTC
Updated: October 26, 2026 at 10:10 PM UTC
1 product affected across 1 vendorHomeBox

Using homebox by sysadminsmedia?

Get instant alerts when new vulnerabilities affect homebox - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.1
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

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ID remained permanently assigned to a user after being invited to a group, even after their access to that group was revoked.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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.25.0
Affected range stops below 0.25.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/sysadminsmedia/homebox/releases/tag/v0.25.0

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.1HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-708

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card