CVE-2026-59893: sqlparse inefficient regex handling in dollar-quoted literals

CVE-2026-59893 · Severity: high · CVSS 7.5 · Published 2026-08-17

sqlparse is a SQL parser library used by many Python applications to parse and format SQL queries. A flaw in its regex pattern matching allows attackers to submit specially crafted SQL text with many unmatched dollar-quote delimiters, causing the parser to consume excessive CPU resources in a quadratic time pattern. Applications that accept user-supplied SQL—such as web interfaces, database tools, or query formatters—can be forced to hang or become unresponsive, disrupting service for legitimate users without requiring authentication.

Technologies: sqlparse (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-59893 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-59893 being exploited in the wild.
How severe is CVE-2026-59893?
High severity, with a CVSS score of 7.5, published 17 August 2026.
Which products and versions are affected?
sqlparse (PyPI) <= 0.5.6.dev0, ECOSYSTEM:introduced=0,fixed=0.6.0.
Is there a fix for CVE-2026-59893?
Yes. sqlparse (PyPI): upgrade to 0.6.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-59893 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-59893?
Check whether you run sqlparse (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • sqlparse (PyPI): upgrade to 0.6.0 or later
    pip install "sqlparse>=0.6.0"

Technical details

The vulnerability is a Regular Expression Denial of Service (ReDoS) in the dollar-quoted SQL literal pattern at sqlparse/keywords.py:33. The regex uses a backreference (`\1`) to match closing delimiters: `(r'((?<![\w\"\$])\$(?:[_A-ZÀ-Ü]\w*)?\$)[\s\S]*?\1', tokens.Literal)`. When processing SQL with many unique, unmatched opening dollar-quote sequences (e.g., `$a0$x $a1$x $a2$x ...`), the regex engine exhausts the remaining input at each position before backtracking, resulting in O(n²) time complexity. The same issue affects multiline comment patterns (`/*` and `/*+`). The lexer applies all regex patterns at every input character position without timeout or length limits, making the flaw exploitable via any public API (`sqlparse.parse()`, `sqlparse.format()`, `sqlparse.split()`) that accepts user-controlled SQL. Empirical testing confirms 3.3× slowdown when input doubles (n=1000 → n=2000, 0.397s → 1.314s). A patch replacing the backreference approach with deterministic O(n) delimiter matching is available in version 0.6.0.

Affected products

  • andialbrecht sqlparse <= 0.5.6.dev0

Identifiers

  • CVE-2026-59893
  • GHSA-prg7-hcfm-mfcr
  • PYSEC-2026-3698

Timeline

  • 2026-08-13: disclosed: GitHub Security Advisory published
  • 2026-08-17: patched: Fix released in sqlparse 0.6.0

References

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