CVE-2026-100659

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Source
https://cve.org/CVERecord?id=CVE-2026-100659
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-100659.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-100659
Aliases
  • GHSA-q9pg-8h3j-8hvm
Downstream
Published
2026-09-26T13:23:26Z
Modified
2026-10-28T02:31:03Z
Severity
  • 6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Netty 4.2.0 through 4.2.17 HTTP/3 Request Routing Bypass
Details

Netty's HTTP/3 codec (io.netty:netty-codec-http3) in versions 4.2.0.Final through 4.2.17.Final does not enforce the RFC 9114 requirement that the :authority pseudo-header field and a literal host header field, when both present, carry the same value. A remote unauthenticated peer can send a single HEADERS frame containing both fields with differing, attacker-controlled values; the request is accepted and delivered to the application with two conflicting authorities, allowing routing, virtual-host, and access-control decisions to be bypassed when different components in the request path consult different fields. This issue is fixed in 4.2.18.Final.

Database specific 
{
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
        "CWE-444"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/100xxx/CVE-2026-100659.json"
}
References

Affected packages

Git / github.com/netty/netty

Affected ranges

Type
GIT
Repo
https://github.com/netty/netty
Events
Introduced
09e64d259c99be8b5b2a471a78f11e65eb82598a
Fixed
2521f494432e27415a567d3a81a9eb907abf20b3
Database specific
Show details 
{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "4.2.0.Final"
                },
                {
                    "fixed": "4.2.18.Final"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StandardRange"
        }
    ]
}

Affected versions

netty-4.*
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-4.2.17.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
Other
netty-clang-bin

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-100659.json"