CVE-2023-43665
MEDIUMCVE-2023-43665 is a medium-severity (CVSS 5.9) CWE-1284 vulnerability in django. O3 Security confirms whether CVE-2023-43665 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Django Denial-of-service in django.utils.text.Truncator
Blast Radius
django🐍django🐍djangoReal-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
In Django 3.2 before 3.2.22, 4.1 before 4.1.12, and 4.2 before 4.2.6, the django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | django | ≥ 3.2a1&&< 3.2.22 | 3.2.22 |
| 🐍PyPI | django | ≥ 4.1a1&&< 4.1.12 | 4.1.12 |
| 🐍PyPI | django | ≥ 4.2a1&&< 4.2.6 | 4.2.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for django. 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 django to 3.2.22 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-43665 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-2023-43665 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-2023-43665. 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-2023-43665 in your dependencies?
O3 detects CVE-2023-43665 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.