What’s Vulnerable › Vulnerabilities

CVE-2026-33209: Avo has a XSS vulnerability on `return_to` param

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-03-20 · updated 2026-06-17
• Weakness: CWE-79

Description

Avo is a framework to create admin panels for Ruby on Rails apps. Prior to version 3.30.3, a reflected cross-site scripting (XSS) vulnerability exists in the return_to query parameter used in the avo interface. An attacker can craft a malicious URL that injects arbitrary JavaScript, which is executed when he clicks a dynamically generated navigation button. This issue has been patched in version 3.30.3.

Affected products

• avo-hq avo: before 3.30.3 — fixed in 3.30.3

How to fix

Upgrade to a fixed version: avo-hq avo 3.30.3. Check the vendor advisory for mitigations.

References

• https://github.com/avo-hq/avo/commit/4453d39ddc6309f3bc8ada73ef21e1971112de7d
• https://github.com/avo-hq/avo/pull/4330
• https://github.com/avo-hq/avo/releases/tag/v3.30.3
• https://github.com/avo-hq/avo/security/advisories/GHSA-762r-27w2-q22j

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