Quick answers
- Is CVE-2026-93575 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-93575 being exploited in the wild.
- How severe is CVE-2026-93575?
- 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-2026-93575?
- 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-2026-93575 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-93575?
- 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 MqttDecoder in Netty fails to properly validate the relationship between the 'Properties Length' and 'Remaining Length' fields in MQTT CONNECT packets, allowing an unauthenticated remote attacker to bypass decoder size limits. This vulnerability enables an attacker to trigger OutOfMemoryError conditions via specially crafted MQTT packets, resulting in denial of service. The flaw requires no authentication and can be exploited over the network.
Affected products
- Netty Netty <UNKNOWN>
Timeline
- 2026-09-18: disclosed