How severe is GHSA-5cr9-5jx3-2g39?

GHSA-5cr9-5jx3-2g39 has a CVSS score of 7.3/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-5cr9-5jx3-2g39?

GHSA-5cr9-5jx3-2g39 affects the following packages: avo (RubyGems), avo (RubyGems). Ecosystems affected: RubyGems.

How do I fix GHSA-5cr9-5jx3-2g39?

Update avo to 2.33.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5cr9-5jx3-2g39 is resolved across your whole dependency graph.

How do I detect GHSA-5cr9-5jx3-2g39 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-5cr9-5jx3-2g39 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-5cr9-5jx3-2g39?

O3 pinpoints whether GHSA-5cr9-5jx3-2g39 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-5cr9-5jx3-2g39 actively exploited in the wild?

Yes. There are 1 known exploit references for GHSA-5cr9-5jx3-2g39, 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-5cr9-5jx3-2g39?

GHSA-5cr9-5jx3-2g39 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 42th 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-5cr9-5jx3-2g39?

GHSA-5cr9-5jx3-2g39 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-5cr9-5jx3-2g39 published, and has it been updated?

GHSA-5cr9-5jx3-2g39 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-5cr9-5jx3-2g39

HIGH

avo vulnerable to Stored XSS (Cross Site Scripting) in html content based fields

Also known asCVE-2023-34103

Published

Jun 6, 2023

Updated

Jun 25, 2024

Affected

2 pkgs

Patched

1 / 2

Exploits

1 known

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk42th percentile-0.09%

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

Some avo fields are vulnerable to XSS when rendering html based content.

Details

During the analysis of the web application, a rendered field was discovered that did not filter JS / HTML tags in a safe way and can be abused to execute js code on a client side. The trix field uses the trix editor in the backend to edit rich text data which basically operates with html tags. To display the stored data in a rendered view, the HasHTMLAttributes concern is used. This can be exploited by an attacker to store javascript code in any trix field by intercepting the request and modifying the post data, as the trix editor does not allow adding custom html or js tags on the frontend.

PoC

Adding javascript in the post request which is used when editing a "post" resource (body is declared as a trix field)

Successful execution of JS code on live demo environment

Impact

Unlike non-persistent XSS, persistent XSS does not require a social engineering phase. Victims of this attack do not need to be tricked into clicking a link or something like that. However, by exploiting such a vulnerability on this particular target, attackers may be able to gain access to accounts that require special protection, such as administrators of the web service, which is what Avo is primarily intended to be used for.

Recommendation

The content of a field that contains html code should be sanitized using the according rails helper which uses a whitelist of known-safe tags and attributes. Also this security consideration should be applied to the “as_html” attribute as well because it may contain user controlled input as well.

https://api.rubyonrails.org/classes/ActionView/Helpers/SanitizeHelper.html

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. In a…

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-5cr9-5jx3-2g39 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-5cr9-5jx3-2g39 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-5cr9-5jx3-2g39. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary Some avo fields are vulnerable to XSS when rendering html based content. ### Details During the analysis of the web application, a rendered field was discovered that did not filter JS / HTML tags in a safe way and can be abused to execute js code on a client side. The trix field uses the trix editor in the backend to edit rich text data which basically operates with html tags. To display the stored data in a rendered view, the HasHTMLAttributes concern is used. This can be exploited by an attacker to store javascript code in any trix field by intercepting the request and modifying

O3 Security · Impact-Aware SCA

Is GHSA-5cr9-5jx3-2g39 in your dependencies?

O3 detects GHSA-5cr9-5jx3-2g39 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