Buffer overflow in Clickhouse

CVE-2021-43305

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.

Vulnerability class: Buffer Overflow

EPSS: 0.016 (74.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-43305?
CVE-2021-43305 is a high-severity vulnerability in Clickhouse, classified under Heap-based Buffer Overflow. CVSS score: 8.8/10. Published 2022-03-14.
How severe is CVE-2021-43305?
High severity. CVSS v3 base score is 8.8 out of 10.