CVE-2026-55518: critical vulnerability in avo-hq avo
Avo: Missing Authorization in Avo Association Attach Endpoint Allows Unauthorized Relationship Manipulation and Privilege Escalation
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.6epss 0.4%
Avo is a framework to create admin panels for Ruby on Rails apps. Prior to 3.32.1 and 4.0.0.beta.51, Avo's association attach workflow checks attach_<association>? in the UI and GET /resources/:resource/:id/:related/new path, but the actual write endpoint, POST /resources/:resource/:id/:related, does not run the same authorization check before mutating the association through Avo::AssociationsController#create. An authenticated low-privileged Avo user can bypass hidden or disabled attach controls and directly attach related records to a parent record by sending a crafted POST request, which can lead to privilege escalation and cross-tenant data exposure where associations represent authorization-bearing relationships. This issue is fixed in versions 3.32.1 and 4.0.0.beta.51.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Affected products
avo-hq · avoRelated CVEs — avo-hq avo
In the same product, most dangerous first.
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