Quick answers
- Is CVE-2026-93488 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-93488 being exploited in the wild.
- How severe is CVE-2026-93488?
- High severity, with a CVSS score of 7.5, published 18 September 2026.
- Which products and versions are affected?
- Netty <UNKNOWN>.
- Is there a fix for CVE-2026-93488?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-93488 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-93488?
- Check whether you run Netty at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability exists in SpdySessionHandler, where the localConcurrentStreams parameter defaults to Integer.MAX_VALUE with no API to configure it. An attacker can send repeated SYN_STREAM frames (with FLAG_FIN=0) over a SPDY connection without authentication or user interaction required. Each frame causes unbounded heap and direct memory allocation, triggering JVM OutOfMemoryError and denial of service. The root cause is inadequate stream limit validation in the SPDY protocol handler. A patch is available to enforce reasonable stream concurrency limits and proper cleanup.
Affected products
- Netty Netty <UNKNOWN>
Timeline
- 2026-09-18: disclosed