CVE-2022-3215Network attack vector

HTTP response splitting via unvalidated outbound headers

Published Sep 28, 2022 · Updated May 20, 2025

HTTP response splitting in Apple SwiftNIO 2.41.2 and earlier allows remote attackers to inject HTTP headers and false responses. The NIOHTTP1 response path emits reflected request data in outbound HTTP/1.1 headers without rejecting encoded newline characters. Exploitation requires a server application to place attacker-controlled request data into a response header, enabling security-header bypass, cache poisoning, or cross-site scripting.

CVSS severity5.3
Medium
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

HTTP response splitting in Apple SwiftNIO 2.41.2 and earlier allows remote attackers to inject HTTP headers and false responses. The NIOHTTP1 response path emits reflected request data in outbound HTTP/1.1 headers without rejecting encoded newline characters. Exploitation requires a server application to place attacker-controlled request data into a response header, enabling security-header bypass, cache poisoning, or cross-site scripting.

The record

CVE
CVE-2022-3215
Published
Sep 28, 2022
Updated
May 20, 2025
Vendor
Apple
Product
SwiftNIO
Classifications
CWE-113, CWE-74, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 28, 2022CVE publishedPublication date reported by the CVE source.
  2. May 20, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <=2.41.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · SwiftNIOversion=unspecified <=2.41.2

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
5.3GitHub Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-113Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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