CVE-2026-93492 Io.netty/netty-codec-http2: netty: http/2 hpackencoder dos with large table size
Remote attackers can cause denial of service in Netty HTTP/2 by sending large header table size settings, exhausting CPU and memory resources.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-93492?
CVE-2026-93492 is a medium-severity denial of service vulnerability in Red Hat AMQ Broker 7, published on 18 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A flaw was found in Netty's HTTP/2 HpackEncoder. A remote attacker can exploit this by sending HTTP/2 SETTINGS frames with a very large MAX_HEADER_TABLE_SIZE. This causes the HpackEncoder to store an excessive number of unique headers, leading to increased CPU usage and memory consumption, ultimately resulting in a Denial of Service (DoS).
Weakness: CWE-1035
Which versions are affected by CVE-2026-93492?
How do I fix CVE-2026-93492?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-93492 being exploited?
There is no known exploitation of CVE-2026-93492 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-93492, GHSA-6ff9-6jw2-jrgf, UBUNTU-CVE-2026-93492.