High severity · published Feb 10, 2021
CVE-2021-27186
Fluent Bit 1.6.10 has a NULL pointer dereference when an flb_malloc return value is not validated by flb_avro.c or http_server/api/v1/metrics.c
7.5
CVSS
2%
EPSS
No
On KEV
Description
Fluent Bit 1.6.10 has a NULL pointer dereference when an flb_malloc return value is not validated by flb_avro.c or http_server/api/v1/metrics.c.
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)2.0% · higher than 81% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FB
Fluent Bit · Treasuredata
1.6.10 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27186
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27186
Exploit
https://github.com/fluent/fluent-bit/issues/3044
Exploit
https://github.com/fluent/fluent-bit/pull/3045
Patch
https://github.com/fluent/fluent-bit/pull/3047
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