CVE-2022-3215
SwiftNIO vulnerable to Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
7.5
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.
- Record
CVE-2022-3215- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-113, CWE-74
- Updated
- 2026-11-02
CVE List
7.5
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.
- Record
CVE-2022-3215- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-113
- Updated
- 2026-11-02
EUVDEUVD-2023-1729
7.5
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.
- Record
EUVD-2023-1729- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7fj7-39wj-c64f
5.3
SwiftNIO vulnerable to Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')
NIOHTTP1 and projects using it for generating HTTP responses, including SwiftNIO, 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 a default channel handler that polices outbound headers. This channel handler is added by default to channel pipelines, but can be removed by users if they are doing this validation themselves.
- Record
GHSA-7fj7-39wj-c64f- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-74, CWE-113
- Updated
- 2026-11-02
OSV
7.5
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.
- Record
CVE-2022-3215- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-113
- Updated
- 2026-11-02
OSVGHSA-7fj7-39wj-c64f
5.3
SwiftNIO vulnerable to Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')
NIOHTTP1 and projects using it for generating HTTP responses, including SwiftNIO, 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 a default channel handler that polices outbound headers. This channel handler is added by default to channel pipelines, but can be removed by users if they are doing this validation themselves.
- Record
GHSA-7fj7-39wj-c64f- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-113, CWE-74
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/apple/swift-nioSwiftURL |
2.41.0 up to 2.42.0 | 2.42.0 |
github.com/apple/swift-nioSwiftURL |
2.39.0 up to 2.39.1 | 2.39.1 |
github.com/apple/swift-nioSwiftURL |
before 2.29.1 | 2.29.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2022-3215 is a high vulnerability (CVSS 7.5) in Apple Swiftnio, published September 28, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.66%, the 52nd percentile. Fixed in github.com/apple/swift-nio 2.42.0.
References
github.com/apple/swift-nio/security/advisories/GHSA-7fj7-39wj-c64f
nvd.nist.gov/vuln/detail/CVE-2022-3215
github.com/apple/swift-nio/commit/a16e2f54a25b2af217044e5168997009a505930f
github.com/advisories/GHSA-7fj7-39wj-c64f
github.com/CVEProject/cvelistV5/tree/main/cves/2022/3xxx/CVE-2022-3215.json
github.com/apple/swift-nio