Quick answers
- Is CVE-2026-93564 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-93564 being exploited in the wild.
- How severe is CVE-2026-93564?
- High severity, with a CVSS score of 7.5, published 18 September 2026.
- Which products and versions are affected?
- Netty Netty.
- Is there a fix for CVE-2026-93564?
- 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-2026-93564 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-93564?
- Check whether you run Netty. 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 is a reference-count leak in Netty's HAProxy PROXY-v2 message decoder. When specially crafted PROXY-protocol v2 headers are received, the decoder fails to properly release memory references, causing them to accumulate over time. An unauthenticated attacker on the network can repeatedly send malformed PROXY-v2 messages to trigger this leak, leading to memory exhaustion and eventual denial of service. The attack is network-accessible and requires no prior authentication or user interaction. A fix is expected in an upstream Netty release.
Affected products
- Netty Netty
Timeline
- 2026-09-18: disclosed