Vulnerability · CVE-2026-93558
A flaw was found in Netty's WebSocketServerExtensionHandler.
Published Sep 18, 2026 · catalog updated Oct 15, 2026 · A flaw was found
Check if you run it
No confirmed exploitation is on record for CVE-2026-93558. EPSS is 1.08%. Act only if a listed version of A flaw was found is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (A flaw was found).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.5
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 1.08%
- Remediation
- Advisory link
- Affected products
- See sources for product scope
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.
No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.
How to fix CVE-2026-93558
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-93558. EPSS is 1.08%. Act only if a listed version of A flaw was found is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-1035. EPSS 1.08%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Sep 18, 2026 · NIST NVD
Detected
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 Den
Oct 15, 2026 · NIST NVD
Updated
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 Den
Sources
- CVE.orgVulnerability recordCVE-2026-93558
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-93558
30-day exploitation probability 1.1%
first.org - NIST NVDVulnerability recordCVE-2026-93558
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, consu
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.