{"id":"CVE-2021-43305","aliases":["DEBIAN-CVE-2021-43305","DLA-3176-1","EUVD-2021-30248","GHSA-rjm8-hjq2-73j6","UBUNTU-CVE-2021-43305","USN-6933-1"],"status":"published","title":"Heap buffer overflow in Clickhouse's LZ4 compression codec when parsing a malicious query. There...","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\u003ccopy_amount\u003e(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.","severity":{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.01672,"percentile":0.77153,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-122","CWE-787"],"published":"2022-03-14T00:00:00Z","modified":"2026-10-24T10:31:04Z","fixes":[{"ecosystem":"Debian:12","package":"clickhouse","fixed_in":["18.16.1+ds-7.3"],"sources":["osv"]},{"ecosystem":"Ubuntu:20.04:LTS","package":"clickhouse","fixed_in":["18.16.1+ds-7ubuntu0.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"clickhouse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"18.16.1+ds-7.3"}]}]},{"source":"osv","ecosystem":"Debian:10","package":"clickhouse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"18.16.1+ds-4+deb10u1"}]}],"versions":["18.16.1+ds-4"],"bundled":4},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"clickhouse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"18.16.1+ds-7ubuntu0.1"}]}],"versions":["18.16.1+ds-5","18.16.1+ds-5ubuntu1","18.16.1+ds-5ubuntu2","18.16.1+ds-6ubuntu1","18.16.1+ds-7"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"clickhouse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"18.16.1+ds-7ubuntu0.1"}]}],"versions":["18.16.1+ds-5","18.16.1+ds-5ubuntu1","18.16.1+ds-5ubuntu2","18.16.1+ds-6ubuntu1","18.16.1+ds-7"],"bundled":3}],"products":[{"vendor":"clickhouse","product":"clickhouse"},{"vendor":"debian","product":"debian_linux"},{"vendor":"yandex","product":"clickhouse"}],"references":[{"url":"https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms","tags":["x_transferred","Exploit","Third Party Advisory","evidence"]},{"url":"https://lists.debian.org/debian-lts-announce/2022/11/msg00002.html","tags":["mailing-list","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-43305"},{"url":"https://github.com/advisories/GHSA-rjm8-hjq2-73j6"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-43305","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-43305","tags":["report"]},{"url":"https://github.com/ClickHouse/ClickHouse/commit/2aea1c8d4a5be320365472052d8a48bf69fd9fe9","tags":["report"]},{"url":"https://github.com/ClickHouse/ClickHouse/commit/6d83eacec42c7c403c99804a713a9d38caa4a45d","tags":["report"]},{"url":"https://github.com/ClickHouse/ClickHouse/pull/27136","tags":["report"]},{"url":"https://jfrog.com/blog/7-rce-and-dos-vulnerabilities-found-in-clickhouse-dbms/","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-43305","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-6933-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-42387","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-42388","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-43305","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\u003ccopy_amount\u003e(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.","status":"published","published":"2022-03-14T00:00:00Z","modified":"2024-08-04T03:55:29.085Z","cwes":["CWE-122"],"updated_at":"2026-11-02T14:32:56.689433Z"}],"euvd":[{"id":"EUVD-2021-30248","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\u003ccopy_amount\u003e(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.","status":"published","published":"2022-03-14T00:00:00Z","modified":"2024-08-04T03:55:29Z","updated_at":"2026-11-03T03:24:14.245608Z"}],"ghsa":[{"id":"GHSA-rjm8-hjq2-73j6","title":"Heap buffer overflow in Clickhouse's LZ4 compression codec when parsing a malicious query. There...","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\u003ccopy_amount\u003e(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.","status":"published","published":"2022-03-16T00:00:49Z","modified":"2025-06-25T21:32:05Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-122","CWE-787"],"updated_at":"2026-11-02T15:02:48.872885Z"}],"nvd":[{"id":"CVE-2021-43305","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\u003ccopy_amount\u003e(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.","status":"published","published":"2022-03-14T23:15:08.203Z","modified":"2026-06-17T04:10:49.397Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":6.5,"vector":"AV:N/AC:L/Au:S/C:P/I:P/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-122","CWE-787"],"updated_at":"2026-11-02T14:07:05.198719Z"}],"osv":[{"id":"CVE-2021-43305","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\u003ccopy_amount\u003e(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.","status":"published","published":"2022-03-14T23:15:08.203Z","modified":"2026-10-24T10:31:04.507818611Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:21.877444Z"},{"id":"DEBIAN-CVE-2021-43305","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\u003ccopy_amount\u003e(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.","status":"published","published":"2022-03-14T23:15:08.203Z","modified":"2026-10-23T18:03:27.828223883Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:35.799676Z"},{"id":"UBUNTU-CVE-2021-43305","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\u003ccopy_amount\u003e(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.","status":"published","published":"2022-03-14T23:15:00Z","modified":"2026-02-04T02:36:20.543628Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:29.220315Z"},{"id":"DLA-3176-1","title":"clickhouse - security update","status":"published","published":"2022-11-03T00:00:00Z","modified":"2026-03-09T01:20:25.107353Z","updated_at":"2026-11-02T15:46:11.189256Z"},{"id":"USN-6933-1","title":"clickhouse vulnerabilities","description":"It was discovered that ClickHouse incorrectly handled memory, leading to a\nheap out-of-bounds data read. An attacker could possibly use this issue to\ncause a denial of service, or leak sensitive information.\n(CVE-2021-42387, CVE-2021-41388)\n\nIt was discovered that ClickHouse incorrectly handled memory, leading to a\nheap-based buffer overflow. An attacker could possibly use this issue to\ncause a denial of service, or execute arbitrary code. (CVE-2021-43305)\n","status":"published","published":"2024-07-31T08:17:56Z","modified":"2026-02-10T04:44:43Z","updated_at":"2026-11-02T16:58:17.914523Z"}]}}