CVE-2021-46878

Public Exploit

Description

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.

Category

7.8
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.03%
Third-Party Advisory chromium.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=27742 patch exploit third party advisory issue tracking
https://github.com/fluent/fluent-bit/pull/3115 patch

Frequently Asked Questions

What is the severity of CVE-2021-46878?
CVE-2021-46878 has been scored as a high severity vulnerability.
How to fix CVE-2021-46878?
To fix CVE-2021-46878, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-46878 being actively exploited in the wild?
It is possible that CVE-2021-46878 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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