What’s Vulnerable › Vulnerabilities

CVE-2021-36088

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-07-01 · updated 2026-06-17
• Weakness: CWE-415

Description

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).

Affected products

• FluentBit Fluent Bit: from 1.7.0 through 1.7.4

References

• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=33750
• https://github.com/fluent/fluent-bit/commit/22346a74c07ceb90296be872be2d53eb92252a54
• https://github.com/fluent/fluent-bit/pull/3453
• https://github.com/google/oss-fuzz-vulns/blob/main/vulns/fluent-bit/OSV-2021-702.yaml
• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=33750
• https://github.com/fluent/fluent-bit/commit/22346a74c07ceb90296be872be2d53eb92252a54
• https://github.com/fluent/fluent-bit/pull/3453
• https://github.com/google/oss-fuzz-vulns/blob/main/vulns/fluent-bit/OSV-2021-702.yaml

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