Red HatCVE-2026-93563
Red Hat Netty: denial of service
High7.5CVE-2026-93563 · Published Sep 18, 2026 · updated Sep 25, 2026
A flaw was found in Netty's `SmtpResponseDecoder` component. A remote attacker, acting as a malicious or man-in-the-middle (MITM) SMTP server, could exploit this by sending a specially crafted, unbounded multi-line SMTP response without a terminator. This vulnerability leads to unbounded memory accumulation within the client's Java Virtual Machine (JVM) heap, causing an `OutOfMemoryError` and a denial of service (DoS) due to a process crash.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Red Hat Fuse 7 Product | all versions | No fix yet |
| Red Hat JBoss Enterprise Application Platform 7 Product | all versions | No fix yet |
| all versions | No fix yet | |
| all versions | No fix yet | |
| all versions | No fix yet | |
| Red Hat Single Sign-On 7 Product | all versions | No fix yet |
| Red Hat build of Apache Camel for Spring Boot 4 Product | all versions | No fix yet |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-1035
More Red Hat advisories
All Red Hat| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Sep 18 | Red Hat OpenShift Container Platform 4: server-side request forgery | Critical9.3 | No fix yet |
| Sep 18 | Red Hat Netty: request smuggling | Medium6.5 | No fix yet |
| Sep 18 | Red Hat Netty: request smuggling | Medium6.5 | No fix yet |
| Sep 18 | A flaw was found in cockpit-files | Medium6.1 | No fix yet |
| Sep 18 | Red Hat cockpit-files. This vulnerability: race condition | Medium6.0 | No fix yet |
| Sep 18 | Red Hat cockpit-files: race condition | Medium6.0 | No fix yet |