High severity · published Apr 11, 2023
CVE-2021-46879
An issue was discovered in Treasure Data Fluent Bit 1.7.1, a wrong variable is used to get the msgpack data resulting in a heap overflow in flb_msgpack_gelf_value_ext
7.8
CVSS
0.4%
EPSS
No
On KEV
Description
An issue was discovered in Treasure Data Fluent Bit 1.7.1, a wrong variable is used to get the msgpack data resulting in a heap overflow in flb_msgpack_gelf_value_ext. An attacker can craft a malicious file and tick the victim to open the file with the software, triggering a heap overflow and execute arbitrary code on the target system.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FB
Fluent Bit · Treasuredata
1.7.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-46879
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-46879
Exploit
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=26851
Patch
https://github.com/fluent/fluent-bit/pull/3100
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