How severe is GHSA-6cj3-rc4p-f38f?

No CVSS score has been assigned to GHSA-6cj3-rc4p-f38f yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-6cj3-rc4p-f38f?

GHSA-6cj3-rc4p-f38f affects the following packages: neos/neos (Packagist), neos/neos (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-6cj3-rc4p-f38f?

Update neos/neos to 1.2.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6cj3-rc4p-f38f is resolved across your whole dependency graph.

How do I detect GHSA-6cj3-rc4p-f38f in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for neos/neos. 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-6cj3-rc4p-f38f 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-6cj3-rc4p-f38f?

O3 pinpoints whether GHSA-6cj3-rc4p-f38f 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-6cj3-rc4p-f38f actively exploited in the wild?

No public exploit code has been indexed for GHSA-6cj3-rc4p-f38f yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was GHSA-6cj3-rc4p-f38f published, and has it been updated?

GHSA-6cj3-rc4p-f38f was published on May 17, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-6cj3-rc4p-f38f: Cross-site Scripting vulnerabilities in Ne…

Blast Radius

2 pkgs affected

🐘neos/neos🐘neos/neos

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

Description

It has been discovered that Neos is vulnerable to several XSS attacks. Through these vulnerabilities, an attacker could tamper with page rendering, redirect victims to a fake login page, or capture user credentials (such as cookies). With the potential backdoor upload an attacker could gain access to the server itself, to an extent mainly limited by the server setup.

Reflected Cross-Site Scripting (SXSS) with authentication

A Neos backend user with permission to modify content can insert JavaScript instructions into content elements. The browser will execute the script in "Print" preview mode. A Neos backend user who can modify his profile information ("Title", "First Name", "Last name", "Middle Name", "Other Name") can inject JavaScript instructions in those parameters. Once set up, an administrator who wants to edit this user account will execute the code. Both attack vectors require a valid Neos backend user account.

Reflected Cross-Site Scripting (RXSS) without authentication

A non-persistent XSS using parameters passed during plugin execution is possible. If invalid parameters are passed, an error message may be shown (depending on the context Neos runs in and how the parameters are handled) that contains the unescaped parameter value.

Note: Through the HTML content type the inclusion of arbitrary JavaScript is still possible for users with a valid Neos backend account. If you want to prohibit that, disable the nodetype or restrict access.

Potential backdoor upload

Through an issue with the underlying Flow framework (see the related Flow advisory Flow-SA-2015-001) any editor with access to the Media Management module can upload server side script files (when using Neos 2.0.x). If those scripts are executed by the server when accessed through their public URL, anything not blocked through other means is possible (information disclosure, placement of backdoors, data removal, …).

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`neos/neos`	≥ 1.2.0&&< 1.2.13	1.2.13
🐘Packagist	`neos/neos`	≥ 2.0.0&&< 2.0.4	2.0.4

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for neos/neos. 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 neos/neos to 1.2.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6cj3-rc4p-f38f 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-6cj3-rc4p-f38f 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-6cj3-rc4p-f38f. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

It has been discovered that Neos is vulnerable to several XSS attacks. Through these vulnerabilities, an attacker could tamper with page rendering, redirect victims to a fake login page, or capture user credentials (such as cookies). With the potential backdoor upload an attacker could gain access to the server itself, to an extent mainly limited by the server setup. ### Reflected Cross-Site Scripting (SXSS) with authentication A Neos backend user with permission to modify content can insert JavaScript instructions into content elements. The browser will execute the script in "Print" preview

O3 Security · Impact-Aware SCA

Is GHSA-6cj3-rc4p-f38f in your dependencies?

O3 detects GHSA-6cj3-rc4p-f38f across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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