CVE-2021-42387

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.

CVSS v3 8.1 HIGH
CVSS v2.0 5.5 MEDIUM

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

5.5^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:S/C:P/I:N/A:P

Exploitability : 8.0 / Impact : 4.9

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms	Exploit Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/11/msg00002.html	Mailing List Third Party Advisory
https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms	Exploit Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/11/msg00002.html	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:clickhouse:clickhouse:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

History

25 Jun 2025, 20:49

Type	Values Removed	Values Added
First Time		Clickhouse clickhouse Clickhouse
CPE	cpe:2.3:a:yandex:clickhouse::::::::	cpe:2.3:a:clickhouse:clickhouse::::::::

Information

Published : 2022-03-14 23:15

Updated : 2025-06-25 20:49

NVD link : CVE-2021-42387

Mitre link : CVE-2021-42387

CVE.ORG link : CVE-2021-42387

JSON object : View

Products Affected

clickhouse

clickhouse

debian

debian_linux

CWE

CWE-125

Out-of-bounds Read

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