How severe is CVE-2022-39288?

CVE-2022-39288 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2022-39288?

CVE-2022-39288 affects the following packages: fastify (npm). Ecosystems affected: npm.

How do I fix CVE-2022-39288?

Update fastify to 4.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-39288 is resolved across your whole dependency graph.

How do I detect CVE-2022-39288 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fastify. 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 CVE-2022-39288 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 CVE-2022-39288?

O3 pinpoints whether CVE-2022-39288 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 CVE-2022-39288 actively exploited in the wild?

No public exploit code has been indexed for CVE-2022-39288 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 CVE-2022-39288?

CVE-2022-39288 has an EPSS (Exploit Prediction Scoring System) score of 59.2%, placing it in the 99th 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. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

When was CVE-2022-39288 published, and has it been updated?

CVE-2022-39288 was published on October 10, 2022 and was last updated on April 2, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

CVE-2022-39288

HIGH

Denial of service in Fastify via Content-Type header

Also known asGHSA-455w-c45v-86rg

Published

Oct 10, 2022

Updated

Apr 2, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

59.2%probability of exploitation in next 30 days

High Risk99th percentile+52.95%

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

📦fastify

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

Description

fastify is a fast and low overhead web framework, for Node.js. Affected versions of fastify are subject to a denial of service via malicious use of the Content-Type header. An attacker can send an invalid Content-Type header that can cause the application to crash. This issue has been addressed in commit fbb07e8d and will be included in release version 4.8.1. Users are advised to upgrade. Users unable to upgrade may manually filter out http content with malicious Content-Type headers.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`fastify`	≥ 4.0.0&&< 4.8.1	4.8.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fastify. 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 fastify to 4.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-39288 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 CVE-2022-39288 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 CVE-2022-39288. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

fastify is a fast and low overhead web framework, for Node.js. Affected versions of fastify are subject to a denial of service via malicious use of the Content-Type header. An attacker can send an invalid Content-Type header that can cause the application to crash. This issue has been addressed in commit `fbb07e8d` and will be included in release version 4.8.1. Users are advised to upgrade. Users unable to upgrade may manually filter out http content with malicious Content-Type headers.

O3 Security · Impact-Aware SCA

Is CVE-2022-39288 in your dependencies?

O3 detects CVE-2022-39288 across npm 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