What’s Vulnerable › Vulnerabilities
CVE-2019-9749
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.7% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2019-03-13 · updated 2026-06-17
- Weakness: CWE-681
Description
An issue was discovered in the MQTT input plugin in Fluent Bit through 1.0.4. When this plugin acts as an MQTT broker (server), it mishandles incoming network messages. After processing a crafted packet, the plugin's mqtt_packet_drop function (in /plugins/in_mqtt/mqtt_prot.c) executes the memmove() function with a negative size parameter. That leads to a crash of the whole Fluent Bit server via a SIGSEGV signal.
Affected products
- FluentBit Fluent Bit: through 1.0.4
References
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