How severe is GHSA-vcfc-9wcp-j623?

GHSA-vcfc-9wcp-j623 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-vcfc-9wcp-j623?

GHSA-vcfc-9wcp-j623 affects the following packages: ServiceStack (NuGet). Ecosystems affected: NuGet.

How do I fix GHSA-vcfc-9wcp-j623?

Update ServiceStack to 5.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-vcfc-9wcp-j623 is resolved across your whole dependency graph.

How do I detect GHSA-vcfc-9wcp-j623 in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ServiceStack. 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-vcfc-9wcp-j623 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-vcfc-9wcp-j623?

O3 pinpoints whether GHSA-vcfc-9wcp-j623 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-vcfc-9wcp-j623 actively exploited in the wild?

No public exploit code has been indexed for GHSA-vcfc-9wcp-j623 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.

What is the EPSS score for GHSA-vcfc-9wcp-j623?

GHSA-vcfc-9wcp-j623 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 55th 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-vcfc-9wcp-j623?

GHSA-vcfc-9wcp-j623 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-vcfc-9wcp-j623 published, and has it been updated?

GHSA-vcfc-9wcp-j623 was published on May 24, 2022 and was last updated on November 8, 2023. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-vcfc-9wcp-j623: Cross site scripting attack in ServiceStac…

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk55th percentile+0.65%

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

1 pkg affected

.NETServiceStack

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

Description

ServiceStack ServiceStack Framework 4.5.14 is affected by: Cross Site Scripting (XSS). The impact is: JavaScrpit is reflected in the server response, hence executed by the browser. The component is: the query used in the GET request is prone. The attack vector is: Since there is no server-side validation and If Browser encoding is bypassed, the victim is affected when opening a crafted URL. The fixed version is: 5.2.0.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`ServiceStack`	≥ 4.5.14&&< 5.2.0	5.2.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ServiceStack. 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 ServiceStack to 5.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-vcfc-9wcp-j623 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-vcfc-9wcp-j623 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-vcfc-9wcp-j623. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

ServiceStack ServiceStack Framework 4.5.14 is affected by: Cross Site Scripting (XSS). The impact is: JavaScrpit is reflected in the server response, hence executed by the browser. The component is: the query used in the GET request is prone. The attack vector is: Since there is no server-side validation and If Browser encoding is bypassed, the victim is affected when opening a crafted URL. The fixed version is: 5.2.0.

O3 Security · Impact-Aware SCA

Is GHSA-vcfc-9wcp-j623 in your dependencies?

O3 detects GHSA-vcfc-9wcp-j623 across NuGet 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

GHSA-vcfc-9wcp-j623