Vulnerability in Treasuredata Fluent Bit
CVE-2019-9749
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.017 (75.7th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 76th percentile — 75.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.017 · newest: 0.017 · change: 0.000
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/fluent/fluent-bit/issues/1135 (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-9749?
- CVE-2019-9749 is a high-severity vulnerability in Treasuredata Fluent Bit, classified under Incorrect Conversion between Numeric Types. CVSS score: 7.5/10. Published 2019-03-13.
- How severe is CVE-2019-9749?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2019-9749 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.