High severity · published Mar 13, 2019
CVE-2019-9749
An issue was discovered in the MQTT input plugin in Fluent Bit through 1.0.4
7.5
CVSS
1.7%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.7% · higher than 77% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FB
Fluent Bit · Treasuredata
through 1.0.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-9749
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-9749
Exploit
https://github.com/fluent/fluent-bit/issues/1135
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