CVE-2021-42387

Public Exploit

Description

Heap out-of-bounds read in Clickhouse's LZ4 compression codec when parsing a malicious query. As part of the LZ4::decompressImpl() loop, a 16-bit unsigned user-supplied value ('offset') is read from the compressed data. The offset is later used in the length of a copy operation, without checking the upper bounds of the source of the copy operation.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.15%
Third-Party Advisory jfrog.com Third-Party Advisory debian.org
Affected: yandex clickhouse
Published at:
Updated at:

References

Link Tags
https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms third party advisory exploit
https://lists.debian.org/debian-lts-announce/2022/11/msg00002.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-42387?
CVE-2021-42387 has been scored as a high severity vulnerability.
How to fix CVE-2021-42387?
To fix CVE-2021-42387, 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-2021-42387 being actively exploited in the wild?
It is possible that CVE-2021-42387 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.
What software or system is affected by CVE-2021-42387?
CVE-2021-42387 affects yandex clickhouse.
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