Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty HTTP/2 max header size handling produces an attack similar to HTTP/2 Rapid Reset. There is a setting in the http2 specification called SETTINGS_MAX_HEADER_LIST_SIZE. When a client sends that setting to Netty, it appears that Netty will behave as follows: read the request; proxy the request to the origin; attempt to produce a response; and create an exception while writing the headers for the response. Functionally, this should be similar to the http2 reset attack, but with a different on-the-wire signature. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/50xxx/CVE-2026-50560.json",
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-770"
]
}{
"source": [
"CPE_RANGE",
"REFERENCES"
],
"cpe": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "4.1.135"
},
{
"introduced": "4.2.0"
},
{
"fixed": "4.2.15"
}
]
}