Cyber Resilience

CVE-2021-42390

MediumPublic PoC

Published: 14 March 2022

Published
14 March 2022
Modified
25 June 2025
KEV Added
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Patch
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CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0055 68.4th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-42390 is a medium-severity Divide By Zero (CWE-369) vulnerability in Clickhouse Clickhouse. Its CVSS base score is 6.5 (Medium).

Operationally, ranked in the top 31.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Divide-by-zero in Clickhouse's DeltaDouble compression codec when parsing a malicious query. The first byte of the compressed buffer is used in a modulo operation without being checked for 0.

CWE(s)
CWE-369

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

clickhouse
clickhouse
≤ 21.10.2.15

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References