Process hang via backtracking string-literal regexes
Published Apr 18, 2023 · Updated Nov 3, 2025
Regular expression denial of service in Andi Albrecht sqlparse before 0.4.4 allows attackers to hang a parsing process with crafted SQL. The String.Single and String.Symbol patterns in keywords.py accept overlapping backslash-escape alternatives, causing excessive regex backtracking on unterminated quoted input. Exploitation requires an application or the sqlformat CLI to pass attacker-controlled SQL to parsing or formatting; the resulting CPU exhaustion interrupts only that process.
Summary
What happened
Regular expression denial of service in Andi Albrecht sqlparse before 0.4.4 allows attackers to hang a parsing process with crafted SQL. The String.Single and String.Symbol patterns in keywords.py accept overlapping backslash-escape alternatives, causing excessive regex backtracking on unterminated quoted input. Exploitation requires an application or the sqlformat CLI to pass attacker-controlled SQL to parsing or formatting; the resulting CPU exhaustion interrupts only that process.
The record
- CVE
- CVE-2023-30608
- Published
- Apr 18, 2023
- Updated
- Nov 3, 2025
- Vendor
- Andi Albrecht
- Product
- sqlparse
- Classifications
- CWE-400, CWE-1333, T1499
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 18, 2023CVE publishedPublication date reported by the CVE source.
- Nov 3, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 0.1.15, < 0.4.4
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- GitHub Security Lab sqlparse ReDoS proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo