How severe is GHSA-86h2-2g4g-29qx?

GHSA-86h2-2g4g-29qx has a CVSS score of 8.3/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-86h2-2g4g-29qx?

GHSA-86h2-2g4g-29qx affects the following packages: avo (RubyGems), avo (RubyGems). Ecosystems affected: RubyGems.

How do I fix GHSA-86h2-2g4g-29qx?

Update avo to 2.33.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-86h2-2g4g-29qx is resolved across your whole dependency graph.

How do I detect GHSA-86h2-2g4g-29qx in my RubyGems dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for avo. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-86h2-2g4g-29qx if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-86h2-2g4g-29qx?

O3 pinpoints whether GHSA-86h2-2g4g-29qx is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-86h2-2g4g-29qx actively exploited in the wild?

Yes. There are 1 known exploit references for GHSA-86h2-2g4g-29qx, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for GHSA-86h2-2g4g-29qx?

GHSA-86h2-2g4g-29qx has an EPSS (Exploit Prediction Scoring System) score of 1.6%, placing it in the 73th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-86h2-2g4g-29qx?

GHSA-86h2-2g4g-29qx is classified as Improper Input Validation (CWE-20), CWE-470 (CWE-470). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-86h2-2g4g-29qx published, and has it been updated?

GHSA-86h2-2g4g-29qx was published on June 6, 2023 and was last updated on June 25, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

💎 RubyGems

GHSA-86h2-2g4g-29qx

HIGH

avo possible unsafe reflection / partial DoS vulnerability

Also known asCVE-2023-34102

Published

Jun 6, 2023

Updated

Jun 25, 2024

Affected

2 pkgs

Patched

1 / 2

Exploits

1 known

EPSS Exploitation Probability

via FIRST.org ↗

1.6%probability of exploitation in next 30 days

Lower Risk73th percentile-6.10%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

2 pkgs affected

💎avo💎avo

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.

Description

Summary

The polymorphic field type stores the classes to operate on when updating a record with user input, and does not validate them in the back end. This can lead to unexpected behavior, remote code execution, or application crashes when viewing a manipulated record.

Details

After reviewing the polymorphic field implementation and performing some black box approaches, we identified a potential security issue related to the use of safe_constantize / constantize. This Rails functionality is capable of searching for classes within the Rails context and returning the class for further use. Because Avo does not validate user input when updating or creating a new polymorphic resource, it is possible to create database entries with completely different or invalid class names than the preselected ones. Avo assumes that the class specified by the user request is a valid one and attempts to work with it, which may result in dangerous behavior and code execution.

PoC

In the test scenario we choose the demo app and the review resource which has a polymorphic reviewable field.

Intercepting the request and switching the review[reviewable_type] from “Fish” to “File” which is a real class inside Rails

Corrupting the database with unusable classes will cause a crash at the application while viewing the new record or the index view (partial DoS)

Manual delete the corrupted resource in order to recover the applications functionality

Of course it is possible to use other class names or namespaces. The local development environment displays the backend error message when visiting a corrupted record. Avo is trying to apply a scope to this class that does not exist.

Specifying an invalid class name in the parameter will cause the application to crash again while trying constanize the provided string

Impact

The final exploitation of this vulnerability requires more time than is provided in this assessment, but initial testing of the post request shows the potential critical risk. The classes could be instantiated at any point in the code and this could also lead to code execution.

Recommendation

Avo should be configured to never trust user-supplied input, especially when defining classes for records. In this particular case, Avo can evaluate the options list given for the polymorphic field and only allow strings from that list. With this white-list approach, an attacker cannot supply unintended classes.

Affected Packages

2 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
💎RubyGems	`avo`	all versions	2.33.3
💎RubyGems	`avo`	≥ 3.0.0.pre1	No fix

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Avo is an open source ruby on rails admin panel creation framework. The …

github.comNVDJun 2023

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for avo. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update avo to 2.33.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-86h2-2g4g-29qx is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-86h2-2g4g-29qx is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-86h2-2g4g-29qx. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary The polymorphic field type stores the classes to operate on when updating a record with user input, and does not validate them in the back end. This can lead to unexpected behavior, remote code execution, or application crashes when viewing a manipulated record. ### Details After reviewing the polymorphic field implementation and performing some black box approaches, we identified a potential security issue related to the use of safe_constantize / constantize. This Rails functionality is capable of searching for classes within the Rails context and returning the class for further

O3 Security · Impact-Aware SCA

Is GHSA-86h2-2g4g-29qx in your dependencies?

O3 detects GHSA-86h2-2g4g-29qx across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works