CVE-2021-43304: Heap buffer overflow in Clickhouse's LZ4 compression codec when parsing a malicious query. There is no verification that the copy operations in the…

PriorityP352high8.8CVSS 3.1

AVNACLPRLUINSUCHIHAH

EPSS

1.65%

73.5th percentile

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(op, ip, copy_end), don’t exceed the destination buffer’s limits.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
clickhouse	clickhouse	< 21.10.2.15	21.10.2.15
clickhouse	clickhouse	>= 0 < 18.16.1+ds-7.2+deb11u1	18.16.1+ds-7.2+deb11u1
clickhouse	clickhouse	>= 0 < 18.16.1+ds-7.3	18.16.1+ds-7.3
debian	clickhouse	< clickhouse 18.16.1+ds-7.3 (bookworm)	clickhouse 18.16.1+ds-7.3 (bookworm)
debian	debian_linux	—	—
yandex	clickhouse	>= unspecified < 21.10.2.15-stable	21.10.2.15-stable

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvdv2.06.5MEDIUMAV:N/AC:L/Au:S/C:P/I:P/A:P

osv8.8HIGH

vendor_debian8.8HIGH

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