How severe is CVE-2022-3215?

CVE-2022-3215 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2022-3215?

CVE-2022-3215 affects the following packages: github.com/apple/swift-nio (SwiftURL), github.com/apple/swift-nio (SwiftURL), github.com/apple/swift-nio (SwiftURL). Ecosystems affected: SwiftURL.

How do I fix CVE-2022-3215?

Update github.com/apple/swift-nio to 2.42.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-3215 is resolved across your whole dependency graph.

How do I detect CVE-2022-3215 in my SwiftURL dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/apple/swift-nio. 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-2022-3215 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-2022-3215?

O3 pinpoints whether CVE-2022-3215 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-2022-3215 actively exploited in the wild?

No public exploit code has been indexed for CVE-2022-3215 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-2022-3215?

CVE-2022-3215 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 41th 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.

When was CVE-2022-3215 published, and has it been updated?

CVE-2022-3215 was published on September 28, 2022 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2022-3215: swift-nio Cross-Site Scripting (High 7.5)

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk41th percentile+0.29%

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

3 pkgs affected

📦github.com/apple/swift-nio📦github.com/apple/swift-nio📦github.com/apple/swift-nio

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

Description

NIOHTTP1 and projects using it for generating HTTP responses can be subject to a HTTP Response Injection attack. This occurs when a HTTP/1.1 server accepts user generated input from an incoming request and reflects it into a HTTP/1.1 response header in some form. A malicious user can add newlines to their input (usually in encoded form) and "inject" those newlines into the returned HTTP response. This capability allows users to work around security headers and HTTP/1.1 framing headers by injecting entirely false responses or other new headers. The injected false responses may also be treated as the response to subsequent requests, which can lead to XSS, cache poisoning, and a number of other flaws. This issue was resolved by adding validation to the HTTPHeaders type, ensuring that there's no whitespace incorrectly present in the HTTP headers provided by users. As the existing API surface is non-failable, all invalid characters are replaced by linear whitespace.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
📦SwiftURL	`github.com/apple/swift-nio`	≥ 2.41.0&&< 2.42.0	2.42.0
📦SwiftURL	`github.com/apple/swift-nio`	≥ 2.39.0&&< 2.39.1	2.39.1
📦SwiftURL	`github.com/apple/swift-nio`	all versions	2.29.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/apple/swift-nio. 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 github.com/apple/swift-nio to 2.42.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-3215 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-2022-3215 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-2022-3215. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

NIOHTTP1 and projects using it for generating HTTP responses can be subject to a HTTP Response Injection attack. This occurs when a HTTP/1.1 server accepts user generated input from an incoming request and reflects it into a HTTP/1.1 response header in some form. A malicious user can add newlines to their input (usually in encoded form) and "inject" those newlines into the returned HTTP response. This capability allows users to work around security headers and HTTP/1.1 framing headers by injecting entirely false responses or other new headers. The injected false responses may also be treated a

O3 Security · Impact-Aware SCA

Is CVE-2022-3215 in your dependencies?

O3 detects CVE-2022-3215 across SwiftURL 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

CVE-2022-3215