CVE-2026-93558

Full vulnerability record from the local CVENow database.
Description

A flaw was found in Netty's WebSocketServerExtensionHandler. A remote, unauthenticated attacker can exploit this vulnerability by using HTTP/1.1 pipelining to send requests faster than the application can respond. This leads to an unbounded growth of a per-connection queue, consuming excessive memory. Eventually, this can cause the Java Virtual Machine (JVM) to exhaust its heap, resulting in a Denial of Service (DoS) for the affected server.
Severity
HIGH
CVSS score
7.5 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
[email protected]
Published
2026-09-18 15:17:19.590000
Last modified
2026-11-06 17:20:04.293000
View original CVE JSON
{
  "id": "CVE-2026-93558",
  "sourceIdentifier": "[email protected]",
  "published": "2026-09-18T15:17:19.590",
  "lastModified": "2026-11-06T17:20:04.293",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
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      "value": "A flaw was found in Netty's WebSocketServerExtensionHandler. A remote, unauthenticated attacker can exploit this vulnerability by using HTTP/1.1 pipelining to send requests faster than the application can respond. This leads to an unbounded growth of a per-connection queue, consuming excessive memory. Eventually, this can cause the Java Virtual Machine (JVM) to exhaust its heap, resulting in a Denial of Service (DoS) for the affected server."
    }
  ],
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