CVE-2021-32839
HIGHStripComments filter contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service)
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
sqlparseReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
sqlparse is a non-validating SQL parser module for Python. In sqlparse versions 0.4.0 and 0.4.1 there is a regular Expression Denial of Service in sqlparse vulnerability. The regular expression may cause exponential backtracking on strings containing many repetitions of '\r\n' in SQL comments. Only the formatting feature that removes comments from SQL statements is affected by this regular expression. As a workaround don't use the sqlformat.format function with keyword strip_comments=True or the --strip-comments command line flag when using the sqlformat command line tool. The issues has been fixed in sqlparse 0.4.2.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | sqlparse | ≥ 0.4.0&&< 0.4.2 | 0.4.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for sqlparse. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update sqlparse to 0.4.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-32839 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2021-32839 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2021-32839. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2021-32839 in your dependencies?
O3 detects CVE-2021-32839 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.