PYSEC-2026-3699 sqlparse: TokenList.__init__ materializes O(subtree) value per group, causing CPU DoS before depth/token caps trigger

Summary sqlparse ships hard limits MAXGROUPINGDEPTH=100, MAXGROUPINGTOKENS=10000 intended to bound parsing work on attacker-supplied SQL, but the path that reaches those limits is itself Ondepth per token-group construction. A 1-2 KB SQL payload e.g. SELECT 1 ... with 500-2000 nesting levels, or ...

sqlparse: TokenList.__init__ materializes O(subtree) value per group, causing CPU DoS before depth/token caps trigger

Summary sqlparse ships hard limits MAXGROUPINGDEPTH=100, MAXGROUPINGTOKENS=10000 intended to bound parsing work on attacker-supplied SQL, but the path that reaches those limits is itself Ondepth per token-group construction. A 1-2 KB SQL payload e.g. SELECT 1 ... with 500-2000 nesting levels, or ...

sqlparse parsing heavily nested list leads to Denial of Service

Summary Passing a heavily nested list to sqlparse.parse leads to a Denial of Service due to RecursionError. Details + PoC Running the following code will raise Maximum recursion limit exceeded exception: py import sqlparse sqlparse.parse'' 10000 + '' 10000 We expect a traceback of RecursionError:...