Improper Input Validation Affecting netty package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published26 Aug 2026
- disclosed24 Aug 2026
Introduced: 24 Aug 2026
NewCVE-2026-76816 (opens in a new tab)How to fix?
There is no fixed version for Echo:latest netty.
NVD Description
Note: Versions mentioned in the description apply only to the upstream netty package and not the netty package as distributed by Echo.
See How to fix? for Echo:latest relevant fixed versions and status.
Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.137.Final and 4.2.17.Final, MqttEncoder does not validate client identifiers, will topics, usernames, and PUBLISH topic names before encoding, allowing prohibited null bytes in MQTT UTF-8 string fields and potentially causing routing, access-control, or identity mismatches in downstream brokers. The vulnerability is exploitable when an application uses Netty's MQTT encoder to construct messages from user-controlled input. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.