CVE-2021-42389
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first...
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first byte of the compressed buffer is used in a modulo operation without being checked for 0.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first byte of the compressed buffer is used in a modulo operation without being checked for 0.
- Record
CVE-2021-42389- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 4.0 Medium
AV:N/AC:L/Au:S/C:N/I:N/A:P - Weakness
- CWE-369
- Updated
- 2026-11-02
CVE List No score
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first byte of the compressed buffer is used in a modulo operation without being checked for 0.
- Record
CVE-2021-42389- Weakness
- CWE-369
- Updated
- 2026-11-02
EUVDEUVD-2021-29360 No score
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first byte of the compressed buffer is used in a modulo operation without being checked for 0.
- Record
EUVD-2021-29360- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-xfh5-vqx3-c7p9
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first...
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first byte of the compressed buffer is used in a modulo operation without being checked for 0.
- Record
GHSA-xfh5-vqx3-c7p9- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-369
- Updated
- 2026-11-02
OSV
Divide-by-zero in Clickhouse's Delta compression codec when parsing a malicious query. The first byte of the compressed buffer is used in a modulo operation without being checked for 0.
- Record
CVE-2021-42389- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-42389 is a medium vulnerability (CVSS 6.5) in Clickhouse, published March 14, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.26%, the 69th percentile. No source names a fixed version.