How severe is GHSA-4v9f-r55g-g6hc?

GHSA-4v9f-r55g-g6hc has a CVSS score of 7.6/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-4v9f-r55g-g6hc?

GHSA-4v9f-r55g-g6hc affects the following packages: prefect (PyPI), prefect (PyPI). Ecosystems affected: PyPI.

How do I fix GHSA-4v9f-r55g-g6hc?

Update prefect to 3.0.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4v9f-r55g-g6hc is resolved across your whole dependency graph.

How do I detect GHSA-4v9f-r55g-g6hc in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for prefect. 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-4v9f-r55g-g6hc 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-4v9f-r55g-g6hc?

O3 pinpoints whether GHSA-4v9f-r55g-g6hc 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-4v9f-r55g-g6hc actively exploited in the wild?

No public exploit code has been indexed for GHSA-4v9f-r55g-g6hc 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-4v9f-r55g-g6hc?

GHSA-4v9f-r55g-g6hc has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 6th 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-4v9f-r55g-g6hc?

GHSA-4v9f-r55g-g6hc is classified as CWE-346 (CWE-346). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-4v9f-r55g-g6hc published, and has it been updated?

GHSA-4v9f-r55g-g6hc was published on March 20, 2025 and was last updated on March 26, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-4v9f-r55g-g6hc: prefect (High 7.6)

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk6th percentile+0.07%

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

🐍prefect🐍prefect

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

Description

A CORS (Cross-Origin Resource Sharing) misconfiguration in prefecthq/prefect prior to version 3.0.3 allows unauthorized domains to access sensitive data. This vulnerability can lead to unauthorized access to the database, resulting in potential data leaks, loss of confidentiality, service disruption, and data integrity risks.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`prefect`	≥ 3.0.0rc1&&< 3.0.3	3.0.3
🐍PyPI	`prefect`	all versions	2.20.17

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for prefect. 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 prefect to 3.0.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4v9f-r55g-g6hc 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-4v9f-r55g-g6hc 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-4v9f-r55g-g6hc. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

A CORS (Cross-Origin Resource Sharing) misconfiguration in prefecthq/prefect prior to version 3.0.3 allows unauthorized domains to access sensitive data. This vulnerability can lead to unauthorized access to the database, resulting in potential data leaks, loss of confidentiality, service disruption, and data integrity risks.

O3 Security · Impact-Aware SCA

Is GHSA-4v9f-r55g-g6hc in your dependencies?

O3 detects GHSA-4v9f-r55g-g6hc across PyPI 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-4v9f-r55g-g6hc