Quick answers
- Is CVE-2026-42205 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-42205 being exploited in the wild.
- How severe is CVE-2026-42205?
- High severity, with a CVSS score of 8.8, published 8 May 2026.
- Which products and versions are affected?
- avo (RubyGems) < 3.31.2, ECOSYSTEM:introduced=0,fixed=3.31.2.
- Is there a fix for CVE-2026-42205?
- Yes. avo (RubyGems): upgrade to 3.31.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-42205 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-42205?
- Check whether you run avo (RubyGems) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- avo (RubyGems): upgrade to 3.31.2 or later
bundle update avo
Technical details
A broken access control vulnerability exists in the `ActionsController` of the Avo framework (v3.x) due to insecure action lookup logic in the `action_class` method. The controller identifies the action class to execute by searching through all descendants of `Avo::BaseAction` based on a user-provided `action_id` parameter, without verifying if that action is registered for the specific resource context in the request URL. An authenticated attacker can exploit this by sending a POST request to a legitimate resource endpoint (e.g., posts) while specifying a sensitive action ID (e.g., ToggleAdmin) and a target record ID. This allows for privilege escalation and unauthorized data manipulation across the application. The issue is fixed in version 3.31.2.
Affected products
- avo-hq avo < 3.31.2
Identifiers
- CVE-2026-42205
- GHSA-qc5p-3mg5-9fh8
Timeline
- 2026-04-20: disclosed: Advisory published by vendor
- 2026-04-24: advisory: GitHub Advisory published
- 2026-05-08: other: NVD published date