CVE-2026-93558: Netty's WebSocketServerExtensionHandler · CWE-1035
Affects nettySource GCVE Database
Not known to be exploited · CVSS 7.5 High.
Data as of 8 Nov 2026, 23:24 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 7.5 |
|---|
- EPSS
- 1.2% chance of exploitation in 30 days – higher than 68% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 18 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 8 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10nettypkg:deb/ubuntu/netty?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu Pro 26.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/resoluteOther threats | Affected
| Fixed in– |
Ubuntu Pro 24.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/nobleOther threats | Affected
| Fixed in– |
Ubuntu Pro 22.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/jammyOther threats | Affected
| Fixed in– |
Ubuntu Pro 20.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/focalOther threats | Affected
| Fixed in– |
Ubuntu Pro 18.04 LTSnettypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
An official security update is available from Red Hat as part of the Red Hat build of Quarkus 3.33.3.SP2 release, which addresses this vulnerability. Users are advised to apply this update to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Description
CVE-2026-93558 is a denial of service vulnerability in Netty's WebSocketServerExtensionHandler component used by Red Hat Build of Apache Camel 3.33.3.SP2. It allows a remote unauthenticated attacker to exploit HTTP/1.1 pipelining to cause unbounded growth of the server's per-connection queue, leading to excessive memory consumption and JVM heap exhaustion. This can disrupt service availability due to resource exhaustion. The vendor has released an important security update in Red Hat build of Quarkus 3.33.3.SP2 addressing this and other vulnerabilities.
References
- ubuntu.com/security/CVE-2026-93558 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-93558 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2536932 (opens in a new tab)
- github.com/netty/netty/security/advisories/GHSA-2g37-3h88-55hc (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-93558 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:69440 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:69470 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:70257 (opens in a new tab)