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...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2020-35963- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:P - Weakness
- CWE-787
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2020-35963- Updated
- 2026-11-02
EUVDEUVD-2020-23546 No score
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.
- Record
EUVD-2020-23546- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-h5px-998j-r7c9
flb_gzip_compress in flb_gzip.c in Fluent Bit before 1.6.4 has an out-of-bounds write because it...
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.
- Record
GHSA-h5px-998j-r7c9- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2020-35963- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVBIT-fluent-bit-2020-35963 No score
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.
- Record
BIT-fluent-bit-2020-35963- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
fluent-bitBitnami |
before 1.6.4 | 1.6.4 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-35963 is a high vulnerability (CVSS 7.8) in Treasuredata Fluent Bit, published January 3, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.33%, the 71st percentile. Fixed in fluent-bit 1.6.4.