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.

• CWE-125
• CWE-125

• https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbmsExploit, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/11/msg00002.htmlMailing List, Third Party Advisory
• https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbmsExploit, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/11/msg00002.htmlMailing List, Third Party Advisory

Published

Mar 14, 2022

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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