CVE-2021-36088
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7,4 has a double free in flb_free (called from...
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7.4 has a double free in flb_free (called from flb_parser_json_do and flb_parser_do).
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7.4 has a double free in flb_free (called from flb_parser_json_do and flb_parser_do).
- Record
CVE-2021-36088- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-415
- Updated
- 2026-11-02
CVE List
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7.4 has a double free in flb_free (called from flb_parser_json_do and flb_parser_do).
- Record
CVE-2021-36088- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-415
- Updated
- 2026-11-02
EUVDEUVD-2021-22721
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7.4 has a double free in flb_free (called from flb_parser_json_do and flb_parser_do).
- Record
EUVD-2021-22721- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-89w3-2j93-4g79
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7,4 has a double free in flb_free (called from...
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7,4 has a double free in flb_free (called from flb_parser_json_do and flb_parser_do).
- Record
GHSA-89w3-2j93-4g79- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-415
- Updated
- 2026-11-02
OSV
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7.4 has a double free in flb_free (called from flb_parser_json_do and flb_parser_do).
- Record
CVE-2021-36088- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVBIT-fluent-bit-2021-36088 No score
Fluent Bit (aka fluent-bit) 1.7.0 through 1.7.4 has a double free in flb_free (called from flb_parser_json_do and flb_parser_do).
- Record
BIT-fluent-bit-2021-36088- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
fluent-bitBitnami |
1.7.0 up to 1.7.5 | 1.7.5 |
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-2021-36088 is a critical vulnerability (CVSS 9.8) in Treasuredata Fluent Bit, published July 1, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.38%, the 83rd percentile. Fixed in fluent-bit 1.7.5.
References
bugs.chromium.org/p/oss-fuzz/issues/detail?id=33750
github.com/google/oss-fuzz-vulns/blob/main/vulns/fluent-bit/OSV-2021-702.yaml
nvd.nist.gov/vuln/detail/CVE-2021-36088