CVE Tools
Sign in

CVE-2021-43305

Published: Mar 14, 2022Updated: Jun 25, 2025 Sources: CVE List NVD BDUCWE-122
NVD MITRE
8.8CVSSHIGH
EPSS Score
1.6%
Top 26.6%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available

Description

Heap buffer overflow in Clickhouse's LZ4 compression codec when parsing a malicious query. There is no verification that the copy operations in the LZ4::decompressImpl loop and especially the arbitrary copy operation wildCopy<copy_amount>(op, ip, copy_end), don’t exceed the destination buffer’s limits. This issue is very similar to CVE-2021-43304, but the vulnerable copy operation is in a different wildCopy call.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-122CWE-787

Affected Products

clickhouseyandex
Mixed
Databases / data-warehouse-analytics
clickhouseclickhouse
On-prem
Databases / data-warehouse-analytics
debian linuxdebian
On-premOS
Operating Systems / linux-distro
ClickHouseClickHouse, Inc.
On-prem
Databases / nosql
yandexcommercialRUDatabasesaka clickhouse, yandex browser
clickhouseoss-projectDatabases
debianoss-projectGBOperating Systemsaka debian gnu/linux
clickhouse, inc.commercialUSDatabasesaka clickhouse

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms
jfrog.com
https://lists.debian.org/debian-lts-announce/2022/11/msg00002.html
lists.debian.org
https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms/&#13;
jfrog.com
and 1 more references View all →

Timeline

Published
Mar 14, 2022
Last Updated
Jun 25, 2025

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2021-43305 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows