{"cve":"CVE-2021-42388","nvd":{"published":"2022-03-14T23:15:07.970","modified":"2026-06-17T04:09:44.987","status":"Modified","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 lower bounds of the source of the copy operation.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":8.1},"cwes":["CWE-125"],"references":["https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms","https://lists.debian.org/debian-lts-announce/2022/11/msg00002.html","https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms","https://lists.debian.org/debian-lts-announce/2022/11/msg00002.html"],"products":["clickhouse:clickhouse","debian:debian_linux"],"source":"nvd","synced_at":"2026-10-19T21:29:06.454770966+00:00"},"epss":{"cve":"CVE-2021-42388","score":0.01573,"percentile":0.75417,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}