CVE-2023-30608 in sqlparse
Summary
by MITRE • 04/19/2023
sqlparse is a non-validating SQL parser module for Python. In affected versions the SQL parser contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service). This issue was introduced by commit `e75e358`. The vulnerability may lead to Denial of Service (DoS). This issues has been fixed in sqlparse 0.4.4 by commit `c457abd5f`. Users are advised to upgrade. There are no known workarounds for this issue.
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Analysis
by VulDB Data Team • 04/27/2025
The sqlparse library represents a critical vulnerability in the Python ecosystem through CVE-2023-30608, which manifests as a Regular Expression Denial of Service (ReDoS) flaw within its SQL parsing functionality. This vulnerability specifically targets the regular expression patterns used for parsing SQL statements, creating a potential attack vector that can disrupt service availability. The flaw was introduced through commit e75e358 and remained present in affected versions until it was patched in release 0.4.4 via commit c457abd5f. The vulnerability operates by exploiting inefficient regular expression patterns that can be manipulated by malicious actors to cause exponential execution time, effectively consuming system resources and leading to service unavailability.
The technical implementation of this vulnerability involves the use of regular expressions that are susceptible to catastrophic backtracking when processing specially crafted input strings. This pattern matching behavior creates a scenario where the parsing engine becomes trapped in nested backtracking loops, causing the system to consume excessive CPU cycles and memory resources. The vulnerability directly maps to CWE-400, which categorizes improper input validation leading to resource exhaustion attacks. When an attacker submits maliciously constructed SQL input to an application utilizing vulnerable sqlparse versions, the parser enters a state where it cannot efficiently process the input, resulting in denial of service conditions that can impact the entire application or system.
The operational impact of CVE-2023-30608 extends beyond simple service disruption, as applications relying on sqlparse for database interaction and query parsing become vulnerable to targeted attacks. This vulnerability can be exploited in environments where user input is processed through sqlparse, including web applications, database management tools, and any system that utilizes Python-based SQL parsing capabilities. The attack surface is particularly broad given that sqlparse is a widely used library in Python applications, making it a prime target for adversaries seeking to exploit resource exhaustion vulnerabilities. Organizations running applications that depend on vulnerable versions of sqlparse face potential downtime and service degradation, with the attack requiring minimal sophistication to execute successfully.
Mitigation strategies for this vulnerability center exclusively on upgrading to sqlparse version 0.4.4 or later, which contains the necessary patch to address the ReDoS vulnerability through improved regular expression patterns. The fix implemented in commit c457abd5f demonstrates a direct resolution to the problematic regex constructs that were susceptible to catastrophic backtracking. Organizations should prioritize immediate deployment of this security update across all systems utilizing sqlparse to prevent exploitation. The vulnerability does not have any known workarounds or temporary fixes, as the root cause lies within the core parsing logic itself. Security teams should conduct comprehensive inventory assessments to identify all systems using vulnerable versions and establish remediation schedules to ensure complete coverage of affected applications. The ATT&CK framework categorizes this vulnerability under T1499.004, which involves network denial of service attacks through resource exhaustion, making it a significant concern for organizations maintaining robust security postures.