How severe is CVE-2021-46879?

CVE-2021-46879 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-46879 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-46879?

CVE-2021-46879 affects Treasuredata Fluent Bit. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-46879?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-46879 published?

CVE-2021-46879 was published on 2023-04-11 and last updated on 2026-06-17.

CVE-2021-46879

CVE-2021-46879 is a high-severity vulnerability in Treasuredata Fluent Bit with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Treasuredata Fluent Bit
Published: 2023-04-11
Last modified: 2026-06-17

Description

An issue was discovered in Treasure Data Fluent Bit 1.7.1, a wrong variable is used to get the msgpack data resulting in a heap overflow in flb_msgpack_gelf_value_ext. An attacker can craft a malicious file and tick the victim to open the file with the software, triggering a heap overflow and execute arbitrary code on the target system.

Frequently asked questions

What is CVE-2021-46879?: An issue was discovered in Treasure Data Fluent Bit 1.7.1, a wrong variable is used to get the msgpack data resulting in a heap overflow in flb_msgpack_gelf_value_ext. An attacker can craft a malicious file and tick the victim to open the file with the software, triggering a heap overflow and execute arbitrary code on the target system.
How severe is CVE-2021-46879?: CVE-2021-46879 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-46879 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-46879?: CVE-2021-46879 affects Treasuredata Fluent Bit. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-46879?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-46879 published?: CVE-2021-46879 was published on 2023-04-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:treasuredata:fluent_bit:1.7.1:*:*:*:*:*:*:*

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