Summary
Avo has a XSS vulnerability on return_to param
Description
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.
Impact
This vulnerability may allow execution of arbitrary JavaScript in the context of the application.
Impact varies depending on deployment:
- In unauthenticated setups: exploitable via crafted links sent to users
- In authenticated setups: limited to authenticated users and requires interaction
Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2026-33209? CVE-2026-33209 is a medium-severity cross-site scripting (XSS) vulnerability in avo (rubygems), affecting versions <= 3.30.2. It is fixed in 3.30.3. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
- Which versions of avo are affected by CVE-2026-33209? avo (rubygems) versions <= 3.30.2 is affected.
- Is there a fix for CVE-2026-33209? Yes. CVE-2026-33209 is fixed in 3.30.3. Upgrade to this version or later.
- Is CVE-2026-33209 exploitable, and should I be worried? Whether CVE-2026-33209 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-33209 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-33209? Upgrade
avoto 3.30.3 or later.