medium5.1
CVE-2026-84305
sqlparse: Reindentation of tuple lists causes near-cap quadratic CPU consumption
Impact
sqlparse is a non-validating SQL parser module for Python. Prior to 0.6.0, sqlparse.format(sql, reindent=True) and sqlformat --reindent route attacker-controlled parenthesized tuple lists through ReindentFilter._get_offset() in sqlparse/filters/reindent.py, where _flatten_up_to_token() repeatedly rebuilds and joins the statement prefix. Thousands of offset calculations walk an expanding token tree, producing quadratic CPU consumption for inputs that remain below MAX_GROUPING_TOKENS and causing request delays, reduced throughput, or worker starvation. This issue is fixed in version 0.6.0.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | sqlparse | <= 0.5.5 | 0.6.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-cfqr-cjx5-5jcm
- https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-cfqr-cjx5-5jcm
- https://github.com/andialbrecht/sqlparse/commit/a51df6d9e2d31b44be9adb6bc8732517db6bf96b
- https://github.com/andialbrecht/sqlparse/releases/tag/0.6.0