Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, WebSocket FrameTranscoder.bodyLength rejects extended payload lengths above Integer.MAX_VALUE but permits negative 64-bit lengths. A remote client that completes a WebSocket handshake through an Ember server can send such a frame, causing the decoder to return an empty frame without advancing its input. The decode loop then runs indefinitely, pins a worker at full CPU, and grows an ArrayBuffer without bound, resulting in denial of service. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-1284",
"CWE-835"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/69xxx/CVE-2026-69210.json"
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "0.23.35"
},
{
"introduced": "1.0.0-M1"
},
{
"fixed": "1.0.0-M47"
}
],
"source": [
"AFFECTED_FIELD",
"REFERENCES"
]
}