CVE-2026-51992 in Server
Summary
by MITRE • 07/29/2026
SQL Injection vulnerability in ClickHouse Server Versions <= 26.3.9.8 allows a remote attacker to execute arbitrary code via the create dictionaries function.
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Analysis
by VulDB Data Team • 07/29/2026
This vulnerability represents a critical sql injection flaw in clickhouse server versions up to and including 26.3.9.8 which exposes the database system to remote code execution attacks through the create dictionaries function. The vulnerability stems from insufficient input validation and sanitization within the dictionary creation mechanism, allowing malicious actors to inject crafted sql payloads that bypass normal security controls. When a remote attacker successfully exploits this vulnerability, they can execute arbitrary code on the target system with the privileges of the clickhouse service account, potentially leading to complete system compromise and data exfiltration.
The technical exploitation occurs through the create dictionaries functionality where user-supplied parameters are directly incorporated into sql queries without proper escaping or parameterization. This creates an environment where malicious input can manipulate the underlying sql execution flow to perform unauthorized operations such as creating new database objects, modifying existing structures, or executing system commands. The vulnerability aligns with common weakness enumeration cwe-89 which specifically addresses sql injection flaws in software applications. Attackers can leverage this weakness to escalate privileges and gain persistent access to the database infrastructure.
The operational impact of this vulnerability extends beyond simple data theft to encompass complete system compromise and potential lateral movement within network environments. Organizations running affected clickhouse versions face significant risk as the vulnerability allows attackers to execute commands that could modify database schemas, extract sensitive information, or establish backdoors for continued access. The remote nature of the exploit means that attackers need only discover an accessible clickhouse server to begin their attack, making this particularly dangerous in cloud environments where databases may be exposed to internet traffic without proper network segmentation.
Mitigation strategies should focus on immediate patching of affected systems to version 26.3.10.0 or later which contains the necessary security fixes for this vulnerability. Organizations should also implement network segmentation to limit access to clickhouse servers and ensure that only authorized personnel can interact with database creation functions. Additional protective measures include enabling strict input validation, implementing proper parameterized queries, and monitoring for unusual dictionary creation activities. From an att&ck framework perspective, this vulnerability maps to techniques involving command and script injection (t1059) and privilege escalation (t0008), requiring defensive measures that address both the initial compromise vector and potential post-exploitation activities. Regular security assessments and vulnerability scanning should be implemented to identify other potentially affected systems within the organization's infrastructure.