CVE-2026-55518
Avo: Missing Authorization in Avo Association Attach Endpoint Allows Unauthorized Relationship Manipulation and Privilege Escalation
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| rubygems | avo | <= 3.32.0 | 3.32.1 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-8fq9-273g-6mrg
- https://github.com/avo-hq/avo/security/advisories/GHSA-8fq9-273g-6mrg
- https://nvd.nist.gov/vuln/detail/CVE-2026-55518
- https://github.com/avo-hq/avo/pull/4568
- https://github.com/avo-hq/avo/commit/995928e586fd1788dd496bd51c4dbe4a79cb2b9c
- https://github.com/avo-hq/avo/releases/tag/v3.32.1
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/avo/CVE-2026-55518.yml
- https://www.cve.org/CVERecord?id=CVE-2026-55518