CVE-2026-100666

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2026-100666
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-100666.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-100666
Aliases
  • GHSA-2g6j-r8q9-5hr8
Downstream
Published
2026-09-26T13:23:31Z
Modified
2026-09-27T03:47:24Z
Severity
  • 6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N CVSS Calculator
Summary
Netty 4.2.0 through 4.2.17 Response Desynchronization via HttpServerCodec
Details

Netty's HttpServerCodec (io.netty:netty-codec-http) in versions 4.2.0.Final through 4.2.16.Final and in versions up to and including 4.1.136.Final pairs each outbound response with an inbound request by calling pollMethod() once per response, including for 1xx informational responses. If a client pipelines an HTTP/1.1 GET carrying an Expect: 100-continue header followed by a HEAD request, the 100 Continue response consumes the queued GET method, so the subsequent 200 OK for the GET is paired with HEAD and its body is dropped, while the following 200 OK for the HEAD request is written with a body. This desynchronizes HTTP parsing on the connection: the GET entity is never delivered and the HEAD response body is interpreted as the GET body, resulting in response splitting and unsafe connection reuse. Fixed in 4.2.17.Final and 4.1.137.Final.

Database specific 
{
    "cna_assigner":  "VulnCheck",
    "cwe_ids":  [
        "CWE-444"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/100xxx/CVE-2026-100666.json"
}
References

Affected packages

Git / github.com/netty/netty

Affected ranges

Type
GIT
Repo
https://github.com/netty/netty
Events
Introduced
09e64d259c99be8b5b2a471a78f11e65eb82598a
Fixed
e0789d32c72f46fd2e7c99b6fdbbf7e2f4409e44
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
5471f0a6ffa4ab39db22c468c6c851af4ecae709
Database specific
Show details 
{
    "extracted_events":  [
        {
            "introduced":  "4.2.0.Final"
        },
        {
            "fixed":  "4.2.17.Final"
        },
        {
            "introduced":  "0"
        },
        {
            "fixed":  "4.1.137.Final"
        }
    ],
    "source":  "AFFECTED_FIELD"
}

Affected versions

netty-4.*
netty-4.0.0.Alpha1
netty-4.0.0.Alpha2
netty-4.0.0.Alpha3
netty-4.0.0.Alpha4
netty-4.0.0.Alpha5
netty-4.0.0.Alpha6
netty-4.0.0.Alpha7
netty-4.0.0.Alpha8
netty-4.0.0.Beta1
netty-4.0.0.Beta2
netty-4.0.0.Beta3
netty-4.0.0.CR1
netty-4.0.0.CR2
netty-4.0.0.CR3
netty-4.0.0.CR4
netty-4.0.0.CR5
netty-4.0.0.CR7
netty-4.0.0.CR8
netty-4.0.0.CR9
netty-4.0.0.Final
netty-4.0.1.Final
netty-4.0.10.Final
netty-4.0.11.Final
netty-4.0.12.Final
netty-4.0.13.Final
netty-4.0.14.Beta1
netty-4.0.14.Final
netty-4.0.15.Final
netty-4.0.2.Final
netty-4.0.3.Final
netty-4.0.4.Final
netty-4.0.5.Final
netty-4.0.6.Final
netty-4.0.7.Final
netty-4.0.8.Final
netty-4.1.0.Beta1
netty-4.1.0.Beta2
netty-4.1.0.Beta3
netty-4.1.0.Beta4
netty-4.1.0.Beta5
netty-4.1.0.Beta6
netty-4.1.0.Beta7
netty-4.1.0.Beta8
netty-4.1.0.CR1
netty-4.1.0.CR2
netty-4.1.0.CR3
netty-4.1.0.CR4
netty-4.1.0.CR5
netty-4.1.0.CR6
netty-4.1.0.CR7
netty-4.1.0.Final
netty-4.1.1.Final
netty-4.1.10.Final
netty-4.1.100.Final
netty-4.1.101.Final
netty-4.1.102.Final
netty-4.1.103.Final
netty-4.1.104.Final
netty-4.1.105.Final
netty-4.1.106.Final
netty-4.1.107.Final
netty-4.1.108.Final
netty-4.1.109.Final
netty-4.1.11.Final
netty-4.1.110.Final
netty-4.1.111.Final
netty-4.1.112.Final
netty-4.1.113.Final
netty-4.1.114.Final
netty-4.1.115.Final
netty-4.1.116.Final
netty-4.1.117.Final
netty-4.1.118.Final
netty-4.1.119.Final
netty-4.1.12.Final
netty-4.1.120.Final
netty-4.1.121.Final
netty-4.1.122.Final
netty-4.1.123.Final
netty-4.1.124.Final
netty-4.1.125.Final
netty-4.1.126.Final
netty-4.1.127.Final
netty-4.1.128.Final
netty-4.1.129.Final
netty-4.1.13.Final
netty-4.1.130.Final
netty-4.1.131.Final
netty-4.1.132.Final
netty-4.1.133.Final
netty-4.1.134.Final
netty-4.1.135.Final
netty-4.1.136.Final
netty-4.1.14.Final
netty-4.1.15.Final
netty-4.1.16.Final
netty-4.1.17.Final
netty-4.1.18.Final
netty-4.1.19.Final
netty-4.1.2.Final
netty-4.1.20.Final
netty-4.1.21.Final
netty-4.1.22.Final
netty-4.1.23.Final
netty-4.1.24.Final
netty-4.1.25.Final
netty-4.1.26.Final
netty-4.1.27.Final
netty-4.1.28.Final
netty-4.1.29.Final
netty-4.1.3.Final
netty-4.1.30.Final
netty-4.1.31.Final
netty-4.1.32.Final
netty-4.1.33.Final
netty-4.1.34.Final
netty-4.1.35.Final
netty-4.1.36.Final
netty-4.1.37.Final
netty-4.1.38.Final
netty-4.1.39.Final
netty-4.1.4.Final
netty-4.1.40.Final
netty-4.1.41.Final
netty-4.1.42.Final
netty-4.1.43.Final
netty-4.1.44.Final
netty-4.1.45.Final
netty-4.1.46.Final
netty-4.1.47.Final
netty-4.1.48.Final
netty-4.1.49.Final
netty-4.1.5.Final
netty-4.1.50.Final
netty-4.1.51.Final
netty-4.1.52.Final
netty-4.1.53.Final
netty-4.1.54.Final
netty-4.1.55.Final
netty-4.1.56.Final
netty-4.1.57.Final
netty-4.1.58.Final
netty-4.1.59.Final
netty-4.1.6.Final
netty-4.1.60.Final
netty-4.1.61.Final
netty-4.1.62.Final
netty-4.1.63.Final
netty-4.1.64.Final
netty-4.1.65.Final
netty-4.1.66.Final
netty-4.1.67.Final
netty-4.1.68.Final
netty-4.1.69.Final
netty-4.1.7.Final
netty-4.1.70.Final
netty-4.1.71.Final
netty-4.1.72.Final
netty-4.1.73.Final
netty-4.1.74.Final
netty-4.1.75.Final
netty-4.1.76.Final
netty-4.1.77.Final
netty-4.1.78.Final
netty-4.1.79.Final
netty-4.1.8.Final
netty-4.1.80.Final
netty-4.1.81.Final
netty-4.1.82.Final
netty-4.1.83.Final
netty-4.1.84.Final
netty-4.1.85.Final
netty-4.1.86.Final
netty-4.1.87.Final
netty-4.1.88.Final
netty-4.1.89.Final
netty-4.1.9.Final
netty-4.1.90.Final
netty-4.1.91.Final
netty-4.1.92.Final
netty-4.1.93.Final
netty-4.1.94.Final
netty-4.1.95.Final
netty-4.1.96.Final
netty-4.1.97.Final
netty-4.1.98.Final
netty-4.1.99.Final
netty-4.2.0.Final
netty-4.2.1.Final
netty-4.2.10.Final
netty-4.2.11.Final
netty-4.2.12.Final
netty-4.2.13.Final
netty-4.2.14.Final
netty-4.2.15.Final
netty-4.2.16.Final
netty-4.2.2.Final
netty-4.2.3.Final
netty-4.2.4.Final
netty-4.2.5.Final
netty-4.2.6.Final
netty-4.2.7.Final
netty-4.2.8.Final
netty-4.2.9.Final

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-100666.json"