CVE-2021-46878
highpriority · track · 31EPSS 0.004 · 28 %ileEUUSEPSS · scored 2026-10-27
An issue was discovered in Treasure Data Fluent Bit 1.7.1, erroneous parsing in flb_pack_msgpack_to_json_format leads to type confusion bug that interprets whatever is on the stack as msgpack maps and arrays, leading to use-after-free. This can be used by an attacker to craft a specially craft file and trick the victim opening it using the affect software, triggering use-after-free and execute arbitrary code on the target system.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- BIT-fluent-bit-2021-468782024-03-06vendor · osvUS
An issue was discovered in Treasure Data Fluent Bit 1.7.1, erroneous parsing in flb_pack_msgpack_to_json_format leads to type confusion bug that interprets whatever is on the stack as msgpack maps and arrays, leading to use-after-free. This can be used by an attacker to craft a specially craft file and trick the victim opening it using the affect software, triggering use-after-free and execute arbitrary code on the target system.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=27742cnnvd
- https://cxsecurity.com/cveshow/CVE-2021-46878/cnnvd
- https://github.com/fluent/fluent-bit/pull/3115cnnvd
- https://github.com/fluent/fluent-bit/releases/tag/v2.0.11Patchcnnvd
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=27742enisa_euvd
- https://github.com/fluent/fluent-bit/pull/3115enisa_euvd
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=27742ExploitIssue TrackingPatchThird Party Advisorynvd
- https://github.com/fluent/fluent-bit/pull/3115Patchnvd
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