High severity · published Jan 3, 2021
CVE-2020-35963
flb_gzip_compress in flb_gzip.c in Fluent Bit before 1.6.4 has an out-of-bounds write because it does not use the correct calculation of the maximum gzip data-size expansion
7.8
CVSS
1.3%
EPSS
No
On KEV
Description
flb_gzip_compress in flb_gzip.c in Fluent Bit before 1.6.4 has an out-of-bounds write because it does not use the correct calculation of the maximum gzip data-size expansion.
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)1.3% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FB
Fluent Bit · Treasuredata
before 1.6.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-35963
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-35963
Exploit
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=27261
Release Notes
https://fluentbit.io/announcements/v1.6.4/
Patch
https://github.com/fluent/fluent-bit/commit/cadff53c093210404aed01c4cf586adb8caa07af
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