A flaw was found in Netty's WebSocketServerExtensionHandler. (CVE-2026-93558)
A vulnerability in Netty's WebSocketServerExtensionHandler allows a remote unauthenticated attacker to cause a denial of service by exploiting HTTP/1.1 pipelining to overwhelm the server's per-connection queue, leading to excessive memory consumption and JVM heap exhaustion.
AI Analysis
Technical Summary
CVE-2026-93558 is a denial of service vulnerability in Netty's WebSocketServerExtensionHandler. An attacker can exploit HTTP/1.1 pipelining to send requests faster than the server can process, causing unbounded growth of a per-connection queue. This excessive memory consumption can exhaust the Java Virtual Machine heap, resulting in a denial of service condition on the affected server.
Potential Impact
The vulnerability allows remote unauthenticated attackers to cause a denial of service by exhausting the JVM heap memory through unbounded queue growth, disrupting availability of the affected server. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Until a patch is available, consider limiting HTTP/1.1 pipelining or applying rate limiting to mitigate potential exploitation.
A flaw was found in Netty's WebSocketServerExtensionHandler. (CVE-2026-93558)
Description
A vulnerability in Netty's WebSocketServerExtensionHandler allows a remote unauthenticated attacker to cause a denial of service by exploiting HTTP/1.1 pipelining to overwhelm the server's per-connection queue, leading to excessive memory consumption and JVM heap exhaustion.
CVSS v3.1
Score 7.5high
Affected software
pkg:deb/ubuntu/netty?arch=source&distro=esm-infra-legacy/trustypkg:deb/ubuntu/netty?arch=source&distro=esm-apps-legacy/xenialpkg:deb/ubuntu/netty?arch=source&distro=esm-apps/bionicpkg:deb/ubuntu/netty?arch=source&distro=esm-apps/focalpkg:deb/ubuntu/netty?arch=source&distro=esm-apps/jammypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/noblepkg:deb/ubuntu/netty?arch=source&distro=esm-apps/resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-93558 is a denial of service vulnerability in Netty's WebSocketServerExtensionHandler. An attacker can exploit HTTP/1.1 pipelining to send requests faster than the server can process, causing unbounded growth of a per-connection queue. This excessive memory consumption can exhaust the Java Virtual Machine heap, resulting in a denial of service condition on the affected server.
Potential Impact
The vulnerability allows remote unauthenticated attackers to cause a denial of service by exhausting the JVM heap memory through unbounded queue growth, disrupting availability of the affected server. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Until a patch is available, consider limiting HTTP/1.1 pipelining or applying rate limiting to mitigate potential exploitation.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-93558
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:Pro:14.04:LTS","Ubuntu:Pro:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:Pro:22.04:LTS","Ubuntu:Pro:24.04:LTS","Ubuntu:Pro:26.04:LTS"]
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ab4be2ef7a7c54106eeec27
Added to database: 09/24/2026, 06:07:42 UTC
Last enriched: 09/24/2026, 06:30:05 UTC
Last updated: 09/24/2026, 09:47:33 UTC
Views: 4
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